Method of forming antireflective coatings

ABSTRACT

An antireflective coating may be formed on visible light transmitting materials. The antireflective coating may a stack of two coating layers. The first coating layer may be formed from a composition that includes a metal alkoxide. The first coating layer may be cured by the application of ultraviolet light or heat. The second coating layer may be formed from a second composition that includes an initiator and an ethylenically substituted monomer. The second composition may be cured by the application of ultraviolet light. The antireflective coatings may be applied to a plastic lens or a plastic lens mold.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to eyeglass lenses. Moreparticularly, the invention relates to a lens forming composition,system and method for making photochromic, ultraviolet/visible lightabsorbing, and colored plastic lenses by curing the lens formingcomposition using activating light.

2. Description of the Relevant Art

It is conventional in the art to produce optical lenses by thermalcuring techniques from the polymer of diethylene glycolbis(allyl)-carbonate (DEG-BAC). In addition, optical lenses may also bemade using ultraviolet (“UV”) light curing techniques. See, for example,U.S. Pat. No. 4,728,469 to Lipscomb et al., U.S. Pat. No. 4,879,318 toLipscomb et al., U.S. Pat. No. 5,364,256 to Lipscomb et al., U.S. Pat.No. 5,415,816 to Buazza et al., U.S. Pat. No. 5,529,728 to Buazza etal., U.S. Pat. No. 5,514,214 to Joel et al., U.S. Pat. No. 5,516,468 toLipscomb, et al., U.S. Pat. No. 5,529,728 to Buazza et al., U.S. Pat.No. 5,689,324 to Lossman et al., U.S. Pat. No. 5,928,575 to Buazza, U.S.Pat. No. 5,976,423 to Buazza, U.S. Pat. No. 6,022,498 to Buazza et al.and U.S. patent application Ser. No. 07/425,371 filed Oct. 26, 1989,Ser. No. 08/439,691 filed May 12, 1995, Ser. No. 08/454,523 filed May30, 1995, Ser. No. 08/453,770 filed May 30, 1995, Ser. No. 08/853,134filed May 8, 1997, 08/844,557 filed Apr. 18, 1997, and Ser. No.08/904,289 filed Jul. 31, 1997, all of which are hereby specificallyincorporated by reference.

Curing of a lens by ultraviolet light tends to present certain problemsthat must be overcome to produce a viable lens. Such problems includeyellowing of the lens, cracking of the lens or mold, optical distortionsin the lens, and premature release of the lens from the mold. Inaddition, many of the useful ultraviolet light-curable lens formingcompositions exhibit certain characteristics that increase thedifficulty of a lens curing process. For example, due to the relativelyrapid nature of ultraviolet light initiated reactions, it is a challengeto provide a composition that is ultraviolet light curable to form aneyeglass lens. Excessive exothermic heat tends to cause defects in thecured lens. To avoid such defects, the level of photoinitiator may bereduced to levels below what is customarily employed in the ultravioletcuring art.

While reducing the level of photoinitiator addresses some problems, itmay also cause others. For instance, lowered levels of photoinitiatormay cause the material in regions near an edge of the lens and proximatea gasket wall in a mold cavity to incompletely cure due to the presenceof oxygen in these regions (oxygen is believed to inhibit curing of manylens forming compositions or materials). Uncured lens formingcomposition tends to result in lenses with “wet” edges covered by stickyuncured lens forming composition. Furthermore, uncured lens formingcomposition may migrate to and contaminate the optical surfaces of thelens upon demolding. The contaminated lens is then often unusable.

Uncured lens forming composition has been addressed by a variety ofmethods (see, e.g., the methods described in U.S. Pat. No. 5,529,728 toBuazza et al). Such methods may include removing the gasket and applyingeither an oxygen barrier or a photoinitiator enriched liquid to theexposed edge of the lens, and then re-irradiating the lens with a dosageof ultraviolet light sufficient to completely dry the edge of the lensprior to demolding. During such irradiation, however, higher thandesirable levels of irradiation, or longer than desirable periods ofirradiation, may be required. The additional ultraviolet irradiation mayin some circumstances cause defects such as yellowing in the lens.

The low photoinitiator levels utilized in many ultraviolet curable lensforming compositions may produce a lens that, while fully-cured asmeasured by percentage of remaining double bonds, may not possesssufficient cross-link density on the lens surface to provide desirabledye absorption characteristics during the tinting process.

Various methods of increasing the surface density of such ultravioletlight curable lenses are described in U.S. Pat. No. 5,529,728 to Buazzaet al. In one method, the lens is demolded and then the surfaces of thelens are exposed directly to ultraviolet light. The relatively shortwavelengths (around 254 nm) provided by some ultraviolet light sources(e.g., a mercury vapor lamp) tend to cause the material to cross-linkquite rapidly. An undesirable effect of this method, however, is thatthe lens tends to yellow as a result of such exposure. Further, anycontaminants on the surface of the lens that are exposed to shortwavelengths of high intensity ultraviolet light may cause tint defects.

Another method involves exposing the lens to relatively high intensityultraviolet radiation while it is still within a mold cavity formedbetween glass molds. The glass molds tend to absorb the more effectiveshort wavelengths, while transmitting wavelengths of about 365 nm. Thismethod generally requires long exposure times and often the infraredradiation absorbed by the lens mold assembly will cause prematurerelease of the lens from a mold member. The lens mold assembly may beheated prior to exposure to high intensity ultraviolet light, therebyreducing the amount of radiation necessary to attain a desired level ofcross-link density. This method, however, is also associated with ahigher rate of premature release.

It is well known in the art that a lens mold/gasket assembly may beheated to cure the lens forming composition from a liquid monomer to asolid polymer. It is also well known that such a lens may be thermallypostcured by applying convective heat to the lens after the molds andgaskets have been removed from the lens.

SUMMARY OF THE INVENTION

An embodiment of an apparatus for preparing an eyeglass lens isdescribed. The apparatus includes a coating unit and a lens curing unit.The coating unit may be configured to coat either mold members orlenses. In one embodiment, the coating unit is a spin coating unit. Thelens curing unit may be configured to direct activating light towardmold members. The mold members are part of a mold assembly that may beplaced within the lens curing unit. Depending on the type of lensforming composition used, the apparatus may be used to form photochromicand non-photochromic lenses. The apparatus may be configured to allowthe operation of both the coating unit and the lens curing unitsubstantially simultaneously.

The coating unit may be a spin coating unit. The spin coating unit maycomprise a holder for holding an eyeglass lens or a mold member. Theholder may be coupled to a motor that is configured to rotate theholder. An activating light source may be incorporated into a cover. Thecover may be drawn over the body of the lens curing unit, covering thecoating units. The activating light source, in one embodiment, ispositioned, when the cover is closed, such that activating light may beapplied to the mold member or lens positioned within the coating unit.An activating light source may be an ultraviolet light source, anactinic light source (e.g., a light source producing light having awavelength between about 380 nm to 490 nm), a visible light sourceand/or an infra-red light source. In one embodiment, the activatinglight source is an ultraviolet light source.

The lens forming apparatus may include a post-cure unit. The post-cureunit may be configured to apply heat and activating light to moldassemblies or lenses disposed within the post-cure unit.

The lens forming apparatus may also include a programmable controllerconfigured to substantially simultaneously control the operation of thecoating unit, the lens curing unit and the post-cure unit. The apparatusmay include a number of light probes and temperature probes disposedwithin the coating unit, lens curing unit, and the post-cure unit. Theseprobes preferably relay information about the operation of theindividual units to the controller. The information relayed may be usedto control the operation of the individual units. The operation of eachof the units may also be controlled based on the prescription of thelens being formed. The controller may be configured to control variousoperations of the coating unit, the curing unit, and the post cure unit.

Additionally, the controller provides system diagnostics and informationto the operator of the apparatus. The controller may notify the userwhen routine maintenance is due or when a system error is detected. Thecontroller may also manage an interlock system for safety and energyconservation purposes. The controller may prevent the lamps fromoperating when the operator may be exposed to light from the lamps.

The controller may also be configured to interact with the operator. Thecontroller preferably includes an input device and a display screen. Anumber of operations controlled by the controller, as described above,may be dependent on the input of the operator. The controller mayprepare a sequence of instructions based on the type of lens (clear,ultraviolet/visible light absorbing, photochromic, colored, etc.),prescription, and type of coatings (e.g., scratch resistant, adhesionpromoting, or tint) inputted by an operator.

A variety of lens forming compositions may be cured to form a plasticeyeglass lens in the above described apparatus. Colored lenses,photochromic lenses, and ultraviolet/visible light absorbing colorlesslenses may be formed. The lens forming compositions may be formulatedsuch that the conditions for forming the lens (e.g., curing conditionsand post cure conditions) may be similar without regard to the lensbeing formed. In an embodiment, a clear lens may be formed under similarconditions used to form photochromic lenses by adding a colorless,non-photochromic ultraviolet/visible light absorbing compound to thelens forming composition. The curing process for forming a photochromiclens is such that higher doses of activating light than are typicallyused for the formation of a clear, non-ultraviolet/visible lightabsorbing lens may be required. In an embodiment, ultraviolet/visiblelight absorbing compounds may be added to a lens forming composition toproduce a substantially clear lens under the more intense dosingrequirements used to form photochromic lenses. The ultraviolet/visiblelight absorbing compounds may take the place of the photochromiccompounds, making curing at higher doses possible for clear lenses. Anadvantage of adding the ultraviolet/visible light absorbers to the lensforming composition is that the clear lens formed may offer betterprotection against ultraviolet/visible light rays than a clear lensformed without such compounds.

In an embodiment, a composition that includes two or more photochromiccompounds may further include a light effector composition to produce alens that exhibits an activated color that differs from an activatedcolor produced by the photochromic compounds without the light effectorcomposition. The activated color is defined as the color a lens achieveswhen exposed to a photochromic activating light source (e.g., sunlight).A photochromic activating light source is defined as any light sourcethat produces light having a wavelength that causes a photochromiccompound to become colored. Photochromic activating light is defined aslight that has a wavelength capable of causing a photochromic compoundto become colored. The photochromic activating wavelength band isdefined as the region of light that has a wavelength that causescoloring of photochromic compounds. The light effector composition mayinclude any compound that exhibits absorbance of at least a portion ofthe photochromic activating wavelength band. Light effector compositionsmay include photoinitiators, ultraviolet/visible light absorbers,ultraviolet light stabilizers, and dyes. In this manner, the activatedcolor of a lens may be altered without altering the ratio and orcomposition of the photochromic compounds. By using a light effectorcomposition, a single lens forming composition may be used as a basesolution to which a light effector may be added in order to alter theactivated color of the formed lens.

The addition of a light effector composition that absorbs photochromicactivating light may cause a change in the activated color of the formedlens. The change in activated color may be dependent on the range ofphotochromic activating light absorbed by the light effectorcomposition. The use of different light effector compositions may allowan operator to produce photochromic lenses with a wide variety ofactivated colors (e.g., red, orange, yellow, green, blue, indigo,violet, gray, or brown).

In an embodiment, an ophthalmic eyeglass lens may be made from anactivating light curable lens forming composition comprising a monomercomposition and a photoinitiator composition. The monomer compositionpreferably includes a polyethylenic functional monomer. Preferably, thepolyethylenic functional monomer composition includes an aromaticcontaining polyether polyethylenic functional monomer. In oneembodiment, the polyethylenic functional monomer is preferably anethoxylated bisphenol A di(meth)acrylate.

The monomer composition may include additional monomers to modify theproperties of the formed eyeglass lens and/or the lens formingcomposition. Monomers which may be used in the monomer compositioninclude polyethylenic functional monomers containing groups selectedfrom acrylyl or methacrylyl.

In another embodiment, an ophthalmic eyeglass lens may be made from anactivating light curable lens forming composition comprising a monomercomposition, a photoinitiator composition and a co-initiatorcomposition. An activating light absorbing compound may also be present.An activating light absorbing compound is herein defined as a compoundwhich absorbs at least a portion of the activating light. The monomercomposition preferably includes a polyethylenic functional monomer.Preferably, the polyethylenic functional monomer is an aromaticcontaining polyether polyethylenic functional monomer. In oneembodiment, the polyethylenic functional monomer is preferably anethoxylated bisphenol A di(meth)acrylate.

The co-initiator composition preferably includes amine co-initiators.Preferably, acrylyl amines are included in the co-initiator composition.In one embodiment, the co-initiator composition preferably includes amixture of CN-384 and CN-386.

Examples of activating light absorbing compounds includes photochromiccompounds, UV stabilizers, UV absorbers, and/or dyes.

In another embodiment, the controller is preferably configured to run acomputer software program which, upon input of the eyeglassprescription, will supply the identification markings of the appropriatefront mold, back mold and gasket. The controller may also be configuredto store the prescription data and to use the prescription data todetermine curing conditions. The controller may be configured to operatethe curing unit to produce the appropriate curing conditions.

In one embodiment, the lens forming composition may be irradiated withcontinuous activated light to initiate curing of the lens formingcomposition. Subsequent to initiating the curing, the lens formingcomposition may be treated with additional activating light and heat tofurther cure the lens forming composition.

In another embodiment, the lens forming composition may be irradiatedwith continuous activated light in a heated curing chamber to initiatecuring of the lens forming composition. Subsequent to initiating thecuring, the lens forming composition may be treated with additionalactivating light and heat to further cure the lens forming composition.

In another embodiment, a system for dispensing a heated polymerizablelens forming composition is described. The dispensing system includes abody configured to hold the lens forming composition, a heating systemcoupled to the body for heating the monomer solution, and a valvepositioned proximate an outlet of the body for controlling the flow ofthe lens forming composition out of the body.

A high-volume lens curing apparatus includes at least a first lenscuring unit and a second lens curing unit. The lens forming apparatusmay, optionally, include an anneal unit. A conveyance system may bepositioned within the first and/or second lens curing units. Theconveyance system may be configured to allow a mold assembly to betransported from the first lens curing unit to the second lens curingunit. Lens curing units include an activating light source for producingactivating light. Anneal unit may be configured to apply heat to an atleast partially relive or relax the stresses caused during thepolymerization of the lens forming material. A controller may be coupledto the lens curing units and, if present, an anneal unit, such that thecontroller is capable of substantially simultaneously operating thethree units. The anneal unit may include a conveyor system fortransferring the demolded lenses through the anneal unit.

BRIEF DESCRIPTION OF THE DRAWINGS

The above brief description as well as further objects, features andadvantages of the methods and apparatus of the present invention will bemore fully appreciated by reference to the following detaileddescription of presently preferred but nonetheless illustrativeembodiments in accordance with the present invention when taken inconjunction with the accompanying drawings in which:

FIG. 1 depicts a perspective view of a plastic lens forming apparatus;

FIG. 2 depicts a perspective view of a spin coating unit;

FIG. 3 depicts a cut-away side view of a spin coating unit;

FIG. 4 depicts a perspective view of a plastic lens forming apparatuswith a portion of the body removed;

FIG. 5 depicts a perspective view of the components of a lens curingunit;

FIG. 6 depicts a perspective view of a plastic lens forming apparatuswith a portion of the body removed and the coating units removed;

FIG. 7 depicts a schematic of a fluorescent light ballast system;

FIG. 8 depicts a mold assembly;

FIG. 9 depicts an isometric view of an embodiment of a gasket;

FIG. 10 depicts a top view of the gasket of FIG. 9;

FIG. 11 depicts a cross-sectional view of an embodiment of a mold/gasketassembly;

FIG. 12 depicts an isometric view of an embodiment of a gasket;

FIG. 13 depicts a top view of the gasket of FIG. 12;

FIG. 14 depicts a side view of a cured lens and molds after removal of agasket;

FIG. 15 depicts a post-cure unit;

FIG. 16 depicts chemical structures of acrylated amines;

FIGS. 17-19 depict a front panel of a controller with a display screendepicting various display menus;

FIG. 20 depicts an isometric view of a heated polymerizable lens formingcomposition dispensing system;

FIG. 21 depicts a side view of a heated polymerizable lens formingcomposition dispensing system;

FIGS. 22 and 23 depict cross-sectional side views of a heatedpolymerizable lens forming composition dispensing system;

FIG. 24 depicts a mold assembly for making flat-top bifocal lenses;

FIG. 25 depicts a front view of a lens curing unit;

FIG. 26 depicts a top view of a lens curing unit;

FIG. 27 depicts an isometric view of a high-volume lens curingapparatus;

FIG. 28 depicts a cross-sectional side view of a high-volume lens curingapparatus;

FIG. 29 depicts a cross-sectional top view of a first curing unit of ahigh-volume lens curing apparatus;

FIG. 30 depicts an isometric view of a mold assembly holder;

FIG. 31 depicts an isometric view of a conveyor system for a high-volumelens curing apparatus;

FIG. 32 depicts a cross sectional top view of a high-volume lens curingapparatus;

FIG. 33 depicts a side view of a portion of a conveyor system for ahigh-volume lens curing apparatus;

FIG. 34 depicts a side view of a high-volume lens curing apparatus; and

FIG. 35 depicts a cross -sectional front view of a high-volume lenscuring apparatus.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Apparatus, operating procedures, equipment, systems, methods, andcompositions for lens curing using activating light are available fromOptical Dynamics Corporation in Louisville, Ky.

Referring now to FIG. 1, a plastic lens curing apparatus is generallyindicated by reference numeral 10. As shown in FIG. 1, lens formingapparatus 10 includes at least one coating unit 20, a lens curing unit30, a post-cure unit 40, and a controller 50. In one embodiment,apparatus 10 includes two coating units 20. Coating unit 20 may beconfigured to apply a coating layer to a mold member or a lens. Coatingunit 20 may be a spin coating unit. Lens curing unit 30 includes anactivating light source for producing activating light. As used herein“activating light” means light that may affect a chemical change.Activating light may include ultraviolet light (e.g., light having awavelength between about 300 nm to about 400 nm), actinic light, visiblelight or infrared light. Generally, any wavelength of light capable ofaffecting a chemical change may be classified as activating. Chemicalchanges may be manifested in a number of forms. A chemical change mayinclude, but is not limited to, any chemical reaction that causes apolymerization to take place. In some embodiments the chemical changecauses the formation of an initiator species within the lens formingcomposition, the initiator species being capable of initiating achemical polymerization reaction. The activating light source may beconfigured to direct light toward a mold assembly. Post-cure unit 40 maybe configured to complete the polymerization of plastic lenses.Post-cure unit 40 may include an activating light source and a heatsource. Controller 50 may be a programmable logic controller. Controller50 may be coupled to coating units 20, lens curing unit 30, andpost-cure unit 40, such that the controller is capable of substantiallysimultaneously operating the three units 20, 30, and 40. Controller 50may be a computer.

A coating unit for applying a coating composition to a lens or a moldmember and then curing the coating composition is described in U.S. Pat.No. 4,895,102 to Kachel et al., U.S. Pat. No. 3,494,326 to Upton, andU.S. Pat. No. 5,514,214 to Joel et al. (all of which are incorporatedherein by reference). In addition, the apparatus shown in FIGS. 2 and 3may also be used to apply coatings to lenses or mold members.

FIG. 2 depicts a pair of spin coating units 102 and 104. These spincoating units may be used to apply a scratch resistant coating or a tintcoating to a lens or mold member. Each of the coating units includes anopening through which an operator may apply lenses and lens moldassemblies to a holder 108. Holder 108 may be partially surrounded bybarrier 114. Barrier 114 may be coupled to a dish 115. As shown in FIG.3, the dish edges may be inclined to form a peripheral sidewall 121 thatmerges with barrier 114. The bottom 117 of the dish may be substantiallyflat. The flat bottom may have a circular opening that allows anelongated member 109 coupled to lens holder 108 to extend through thedish 115.

Holder 108 may be coupled to a motor 112 via elongated member 109. Motor112 may be configured to cause rotation of holder 108. In such a case,motor 112 may be configured to cause rotation of elongated member 109,that in turn causes the rotation of holder 108. The coating unit102/104, may also include an electronic controller 140. Electroniccontroller 140 may be coupled to motor 112 to control the rate at whichholder 108 is rotated by motor 112. Electronic controller 140 may becoupled to a programmable logic controller, such as controller 50, shownin FIG. 1. The programmable logic controller may send signals to theelectronic controller to control the rotational speed of holder 108. Inone embodiment, motor 112 is configured to rotate holder 108 atdifferent rates. Motor 112 may be capable of rotating the lens or moldmember at a rate of up to 1500 revolutions per minute (“RPM”).

In one embodiment, barrier 114 has an interior surface that may be madeor lined with an absorbent material such as foam rubber. This absorbentmaterial may be disposable and removable. The absorbent material may beconfigured to absorb any liquids that fall off a lens or mold memberduring use. Alternatively, the interior surface of barrier 114 may besubstantially non-absorbent, allowing any liquids used during thecoating process to move down barrier 114 into dish 115.

Coating units 20, in one embodiment, are positioned in a top portion 12of lens forming apparatus 10, as depicted in FIG. 1. A cover 22 may becoupled to body 14 of the lens forming apparatus to allow top portion 12to be covered during use. A light source 23 may be positioned on aninner surface of cover 22. The light source may include at least onelamp 24, preferably two or more lamps, positioned on the inner surfaceof cover 22. Lamps 24 may be positioned such that the lamps are orientedabove the coating units when cover 22 is closed. Lamps 24 emitactivating light upon the lenses or mold members positioned withincoating units 20. Lamps may have a variety of shapes including, but notlimited to, linear (as depicted in FIG. 1), square, rectangular,circular, or oval. Activating light sources emit light having awavelength that will initiate curing of various coating materials. Forexample, most currently used coating materials may be curable byactivating light having wavelengths in the ultraviolet region, thereforethe light sources should exhibit strong ultraviolet light emission. Thelight sources may also be configured to produce minimal heat during use.Lamps that exhibit strong ultraviolet light emission have a peak outputat a wavelength in the ultraviolet light region, between about 200 nm toabout 400 nm, preferably the peak output is between about 200 nm to 300nm, and more preferably at about 254 nm. In one embodiment, lamps 24 mayhave a peak output in the ultraviolet light region and have relativelylow heat output. Such lamps are commonly known as “germicidal” lamps andany such lamp may be used. A “germicidal” light emitting light with apeak output in the desired ultraviolet region is commercially availablefrom Voltarc, Inc. of Fairfield, Connecticut as model UV-WX G10T5.

An advantage of using a spin coating unit is that lamps of a variety ofshapes may be used (e.g., linear lamps) for the curing of the coatingmaterials. In one embodiment, a coating material is preferably cured ina substantially uniform manner to ensure that the coating is formeduniformly on the mold member or lens. With a spin coating unit, theobject to be coated may be spun at speeds high enough to ensure that asubstantially uniform distribution of light reaches the object duringthe curing process, regardless of the shape of the light source. The useof a spin coating unit preferably allows the use of commerciallyavailable linear light sources for the curing of coating materials.

A switch may be incorporated into cover 22. The switch is preferablyelectrically coupled to light source 23 such that the switch must beactivated prior to turning the light source on. Preferably, the switchis positioned such that closing the cover causes the switch to becomeactivated. In this manner, the lights will preferably remain off untilthe cover is closed, thus preventing inadvertent exposure of an operatorto the light from light source 23.

During use a lens or lens mold assembly may be placed on the lens holder108. The lens holder 108 may include a suction cup connected to a metalbar. The concave surface of the suction cup may be attachable to a faceof a mold or lens, and the convex surface of the suction cup may beattached to a metal bar. The metal bar may be coupled to motor 112. Thelens holder may also include movable arms and a spring assembly that maybe together operable to hold a lens against the lens holder with springtension during use.

As shown in FIG. 4, the curing unit 30 may include an upper light source214, a lens drawer assembly 216, and a lower light source 218. Lensdrawer assembly 216 preferably includes a mold assembly holder 220, morepreferably at least two mold assembly holders 220. Each of the moldassembly holders 220 is preferably configured to hold a pair of moldmembers that together with a gasket form a mold assembly. The lensdrawer assembly 216 is preferably slidingly mounted on a guide. Duringuse, mold assemblies may be placed in the mold assembly holders 220while the lens drawer assembly is in the open position (i.e., when thedoor extends from the front of the lens curing unit). After the moldassemblies have been loaded into the mold holder 220 the door may beslid into a closed position, with the mold assemblies directly under theupper light source 214 and above the lower light source 218. Vents (notshown) may be placed in communication with the lens curing unit to allowa stream of air to be directed toward the mold members when the moldmembers are positioned beneath the upper lamps. An exhaust fan (notshown) may communicate with the vents to improve the circulation of airflowing through the lens curing unit.

As shown in FIGS. 4 and 5, it is preferred that the upper light source214 and lower light source 216 include a plurality of activating lightgenerating devices or lamps 240. Preferably, the lamps are orientedproximate each other to form a row of lights, as depicted in FIG. 4.Preferably, three or four lamps are positioned to provide substantiallyuniform radiation over the entire surface of the mold assembly to becured. The lamps 240, preferably generate activating light. Lamps 240may be supported by and electrically connected to suitable fixtures 242.Lamps 240 may generate either ultraviolet light, actinic light, visiblelight, and/or infrared light. The choice of lamps is preferably based onthe monomers used in the lens forming composition. In one embodiment,the activating light may be generated from a fluorescent lamp. Thefluorescent lamp preferably has a strong emission spectra in the 380 to490 nm region. A fluorescent lamp emitting activating light with thedescribed wavelengths is commercially available from Philips as modelTLD-15W/03. In another embodiment, the lamps may be ultraviolet lights.

In one embodiment, the activating light sources may be turned on and offquickly between exposures. Ballasts 250, depicted in FIG. 6, may be usedfor this function. The ballasts may be positioned beneath the coatingunit. Power supply 252 may also be located proximate the ballasts 250,underneath the coating unit.

Typically, when a fluorescent lamp is turned off the filaments in thelamp will become cool. When the lamp is subsequently turned on, the lampintensity may fluctuate as the filaments are warmed. These fluctuationsmay effect the curing of a lens forming compositions. To minimize theintensity fluctuations of the lamps, a ballasts 250 may allow thestartup of a fluorescent lamp and minimizes the time required tostabilize the intensity of the light produced by the fluorescent lamp.

A number of ballast systems may be used. Ballasts for fluorescent lampstypically serve two purposes. One function is to provide an initial highvoltage arc that will ionize the gases in the fluorescent lamp (knownherein as the “strike voltage”). After the gases are ionized, a muchlower voltage will be required to maintain the ionization of the gases.In some embodiments, the ballast will also limit the current flowthrough the lamp. In some ballast systems, the filaments of a lamp maybe preheated before the starting voltage is sent through the electrodes.

An instant start ballast typically provides a strike voltage of between500-600 V. The electrodes of fluorescent lamps that are used with aninstant start ballast are usually designed for starting withoutpreheating. Instant start ballast allow the fluorescent lamp to beturned on quickly without a significant delay. However, the intensity oflight produced by the fluorescent lamp may fluctuate as the temperatureof the filaments increases.

Rapid start ballasts include a high voltage transformer for providingthe strike voltage and additional windings that supply a low voltage(between about 2 to 4 V) to the filaments to heat the filaments beforethe lamp is started. Because the filaments are already heated, thestrike voltage required to ionize the gases in the lamp are lower thanthose used with an instant start ballast. A rapid start ballasttypically produces a strike voltage of 250 to 400 V. A rapid startballast may be used to minimize fluctuations in the intensity of thelight produced by the lamp. Since the filaments are preheated before thelamp comes on, the time required to heat up the filaments to theirnormal operating temperature is minimal.

Rapid start ballasts typically continually run the heating voltagethrough the filaments during operation of the lamp and when the lampsare switched off. Thus, during long periods when the lamps are not used,the filaments will be maintained in a heated state. This tends to wastepower and increase the operating costs of the apparatus.

To allow more control over the heating of the filaments, a flasherballast system may be used. A schematic drawing of an embodiment of aflasher ballast system is depicted in FIG. 7. In a flasher ballastsystem a fluorescent lamp 712 is electrically coupled to a highfrequency instant start ballast 714 and one or more transformers 716.The high frequency instant start ballast 714 may provide the strikevoltage and perform the current limiting functions once the lamp islighted. High frequency instant start ballasts are available from manydifferent manufacturers including Motorola, Inc. and Hatch Transformers,Inc. Tampa, Fla. The transformers 716 may be electrically coupled to oneor both of the filaments 718 to provide a low voltage (between about 2to about 4 V) to the filaments. This low voltage may heat the filaments718 to a temperature that is close to the operating temperature of thefilaments 718. By heating the filaments before turning the lamp on, theintensity of light produced by the lamp may be stable because thefilaments of the lamp are kept close to the optimum operatingtemperature. Transformers are available from many differentmanufacturers. In one embodiment toroidal transformers may be used tosupply low voltage to the filaments. Toroidal transformers may beobtained from Plitron Manufacturing Inc. Toronto, Ontario, Canada orToroid Corporation of Maryland, Salisbury, Md.

Because the instant start ballast 714 and the transformers 716 areseparate units they may be operated independently of each other. Acontroller 711 may be coupled to both the instant start ballast 714 andthe transformers 716 to control the operation of these devices. Thetransformers 716 may be left on or off when the striking voltage isapplied to the lamp. In some embodiments, controller 711 may turn offthe transformers 716 just before the strike voltage is applied to thelamp. The controller 711 may also monitor the operation of the lamp. Thecontroller 711 may be programmed to turn the transformers 716 on whenthe lamps are switched off, thus maintaining the lamps in a state ofreadiness. To conserve power, the filaments 718 may be warmed only priorto turning on the lamp. Thus, when the controller 711 receives a signalto turn the lamp on, the controller may turn on the transformers 716 towarm the filaments 718, and subsequently turn on the lamp by sending astriking voltage from the instant start ballast 714. The controller maybe configured to turn the transformer off after a predetermined amountof inactivity of the lamps. For example, the controller may beconfigured to receive signals when the lamps are used in a curingprocess. If no such signals are received, the controller may turn offthe lamps (by turning off the instant start ballast), but leave thetransformer on. The lamps may be kept in a state of readiness for apredetermined amount of time. If no signals are received by thecontroller to turn on the lamp, the controller may turn the transformeroff to conserve energy.

In one embodiment, an upper light filter 254 may be positioned betweenupper light source 214 and lens drawer assembly 216, as depicted in FIG.5. A lower light filter 256 may be positioned between lower light source218 and lens drawer assembly 216. The upper light filter 254 and lowerlight filter 256 are shown in FIG. 5 as being made of a single filtermember, however, those of ordinary skill in the art will recognize thateach of the filters may include two or more filter members. Thecomponents of upper light filter 254 and lower light filter 256 arepreferably modified depending upon the characteristics of the lens to bemolded. For instance, in an embodiment for making negative lenses, theupper light filter 254 includes a plate of Pyrex glass that may befrosted on both sides resting upon a plate of clear Pyrex glass. Thelower light filter 256 includes a plate of Pyrex glass, frosted on oneside, resting upon a plate of clear Pyrex glass with a device forreducing the intensity of activating light incident upon the centerportion relative to the edge portion of the mold assembly.

Conversely, in a an alternate arrangement for producing positive lenses,the upper light filter 254 includes a plate of Pyrex glass frosted onone or both sides and a plate of clear Pyrex glass resting upon theplate of frosted Pyrex glass with a device for reducing the intensity ofactivating light incident upon the edge portion in relation to thecenter portion of the mold assembly. The lower light filter 256 includesa plate of clear Pyrex glass frosted on one side resting upon a plate ofclear Pyrex glass with a device for reducing the intensity of activatinglight incident upon the edge portion in relation to the center portionof the mold assembly. In this arrangement, in place of a device forreducing the relative intensity of activating light incident upon theedge portion of the lens, the diameter of the aperture 250 may bereduced to achieve the same result, i.e., to reduce the relativeintensity of activating light incident upon the edge portion of the moldassembly.

It should be apparent to those skilled in the art that each filter 254or 256 could be composed of a plurality of filter members or include anyother means or device effective to reduce the light to its desiredintensity, to diffuse the light and/or to create a light intensitygradient across the mold assemblies. Alternately, in certain embodimentsno filter elements may be used.

In one embodiment, upper light filter 254 or lower light filter 256 eachinclude at least one plate of Pyrex glass having at least one frostedsurface. Also, either or both of the filters may include more than oneplate of Pyrex glass each frosted on one or both surfaces, and/or one ormore sheets of tracing paper. After passing through frosted Pyrex glass,the activating light is believed to have no sharp intensitydiscontinuities. By removing the sharp intensity distributions areduction in optical distortions in the finished lens may be achieved.Those of ordinary skill in the art will recognize that other means maybe used to diffuse the activating light so that it has no sharpintensity discontinuities. In another embodiment, a plastic filter maybe used. The plastic filter may be formed from a substantially clearsheet of plastic. The plastic filter may frosted or non-frosted. Thesubs tantially clear sheet of plastic is formed from a material thatdoes not significantly absorb wavelengths of light that initiate thepolymerization reaction. In one embodiment, the plastic filter may beformed from a sheet of polycarbonate. An example of a polycarbonate thatmay be used is LEXAN polycarbonate, commercially available from GeneralElectric Corporation. In another embodiment, the filter may be formedfrom a borosilicate type glass.

In operation, the apparatus may be appropriately configured for theproduction of positive lenses which are relatively thick at the centeror negative lenses which are relatively thick at the edge. To reduce thelikelihood of premature release, the relatively thick portions of a lensare preferably polymerized at a faster rate than the relatively thinportions of a lens.

The rate of polymerization taking place at various portions of a lensmay be controlled by varying the relative intensity of activating lightincident upon particular portions of a lens. For positive lenses, theintensity of incident activating light is preferably reduced at the edgeportion of the lens so that the thicker center portion of the lenspolymerizes faster than the thinner edge portion of the lens.

It is well known by those of ordinary skill in the art that lens formingmaterials tend to shrink as they cure. If the relatively thin portion ofa lens is allowed to polymerize before the relatively thick portion, therelatively thin portion will tend to be rigid at the time the relativelythick portion cures and shrinks and the lens will either releaseprematurely from or crack the mold members. Accordingly, when therelative intensity of activating light incident upon the edge portion ofa positive lens is reduced relative to the center portion, the centerportion may polymerize faster and shrink before the edge portion isrigid so that the shrinkage is more uniform.

The variation of the relative intensity of activating light incidentupon a lens may be accomplished in a variety of ways. According to onemethod, in the case of a positive lens, a metal plate having an aperturedisposed in a position over the center of the mold assembly may beplaced between the lamps and the mold assembly. The metal plate ispositioned such that the incident activating light falls mainly on thethicker center portion of the lens. In this manner, the polymerizationrate of the center of a positive lens may be accelerated with respect tothe outer edges of the positive lens, which receive less activatinglight. The metal plate may be inserted manually or may be inserted by anautomatic device that is coupled to the controller. In one embodiment,the prescription entered into the controller determines whether themetal plate is placed between the lamps and the mold assembly.

As shown in FIG. 7, the mold assembly 352 may include opposed moldmembers 378, separated by an annular gasket 380 to define a lens moldingcavity 382. The opposed mold members 378 and the annular gasket 380 maybe shaped and selected in a manner to produce a lens having a desireddiopter.

The mold members 378 may be formed of any suitable material that willpermit the passage of activating light. The mold members 378 arepreferably formed of glass. Each mold member 378 has an outer peripheralsurface 384 and a pair of opposed surfaces 386 and 388 with the surfaces386 and 388 being precision ground. Preferably the mold members 378 havedesirable activating light transmission characteristics and both thecasting surface 386 and non-casting surface 388 preferably have nosurface aberrations, waves, scratches or other defects as these may bereproduced in the finished lens.

As noted above, the mold members 378 are preferably adapted to be heldin spaced apart relation to define a lens molding cavity 382 between thefacing surfaces 386 thereof. The mold members 378 are preferably held ina spaced apart relation by a T-shaped flexible annular gasket 380 thatseals the lens molding cavity 382 from the exterior of the mold members378. In use, the gasket 380 may be supported on a portion of the moldassembly holder 220 (shown in FIG. 4).

In this manner, the upper or back mold member 390 has a convex innersurface 386 while the lower or front mold member 392 has a concave innersurface 386 so that the resulting lens molding cavity 382 is preferablyshaped to form a lens with a desired configuration. Thus, by selectingthe mold members 378 with a desired surface 386, lenses with differentcharacteristics, such as focal lengths, may be produced.

Rays of activating light emanating from lamps 240 preferably passthrough the mold members 378 and act on a lens forming material disposedin the mold cavity 382 in a manner discussed below so as to form a lens.As noted above, the rays of activating light may pass through a suitablefilter 254 or 256 before impinging upon the mold assembly 352.

The mold members 378, preferably, are formed from a material that willnot transmit activating light having a wavelength below approximately300 nm. Suitable materials are Schott Crown, S-1 or S-3 glassmanufactured and sold by Schott Optical Glass Inc., of Duryea,Pennsylvania or Corning 8092 glass sold by Corning Glass of Corning,N.Y. A source of flat-top or single vision molds may be Augen Lens Co.in San Diego, Calif.

The annular gasket 380 may be formed of vinyl material that exhibitsgood lip finish and maintains sufficient flexibility at conditionsthroughout the lens curing process. In an embodiment, the annular gasket380 is formed of silicone rubber material such as GE SE6035 which iscommercially available from General Electric. In another preferredembodiment, the annular gasket 380 is formed of copolymers of ethyleneand vinyl acetate which are commercially available from E. I. DuPont deNemours & Co. under the trade name ELVAX7. Preferred ELVAX7 resins areELVAX7 350 having a melt index of 17.3-20.9 dg/min and a vinyl acetatecontent of 24.3-25.7 wt. %, ELVAX7 250 having a melt index of 22.0-28.0dg/min and a vinyl acetate content of 27.2-28.8 wt. %, ELVAX7 240 havinga melt index of 38.0-48.0 dg/min and a vinyl acetate content of27.2-28.8 wt. %, and ELVAX7 150 having a melt index of 38.0-48.0 dg/minand a vinyl acetate content of 32.0-34.0 wt. %. In another embodiment,the gasket may be made from polyethylene. Regardless of the particularmaterial, the gaskets 380 may be prepared by conventional injectionmolding or compression molding techniques which are well-known by thoseof ordinary skill in the art.

FIGS. 9 and 10 present an isometric view and a top view, respectively,of a gasket 510. Gasket 510 may be annular, and is preferably configuredto engage a mold set for forming a mold assembly. Gasket 510 ispreferably characterized by at least four discrete projections 511.Gasket 510 preferably has an exterior surface 514 and an interiorsurface 512. The projections 511 are preferably arranged upon innersurface 512 such that they are substantially coplanar. The projectionsare preferably evenly spaced around the interior surface of the gasketPreferably, the spacing along the interior surface of the gasket betweeneach projection is about 90 degrees. Although four projections arepreferred, it is envisioned that more than four could be incorporated.The gasket 510 may be formed of a silicone rubber material such as GESE6035 which is commercially available from General Electric. In anotherembodiment, the gasket 510 may be formed of copolymers of ethylene andvinyl acetate which are commercially available from E. I. DuPont deNemours & Co. under the trade name ELVAX7. In another embodiment, thegasket 510 may be formed from polyethylene. In another embodiment. thegasket may be formed from a thermoplastic elastomer rubber. An exampleof a thermoplastic elastomer rubber that may be used is, DYNAFLEX G-2780commercially available from GLS Corporation.

As shown in FIG. 11, projections 511 are preferably capable of spacingmold members 526 of a mold set. Mold members 526 may be any of thevarious types and sizes of mold members that are well known in the art.A mold cavity 528 at least partially defined by mold members 526 andgasket 510, is preferably capable of retaining a lens formingcomposition. Preferably, the seal between gasket 510 and mold members526 is as complete as possible. The height of each projection 511preferably controls the spacing between mold members 526, and thus thethickness of the finished lens. By selecting proper gaskets and moldsets, lens cavities may be created to produce lenses of various powers.

A mold assembly consists of two mold members. A front mold member 526 aand a back mold member 526 b, as depicted in FIG. 11. The back moldmember is also known as the convex mold member. The back mold memberpreferably defines the concave surface of a convex lens. Referring backto FIGS. 9 and 10, locations where the steep axis 522 and the flat axis524 of the back mold member 526 b preferably lie in relation to gasket510 have been indicated. In conventional gaskets, a raised lip may beused to space mold members. The thickness of this lip varies over thecircumference of the lip in a manner appropriate with the type of moldset a particular gasket is designed to be used with. In order to havethe flexibility to use a certain number of molds, an equivalent amountof conventional gaskets is typically kept in stock.

However, within a class of mold sets there may be points along the outercurvature of a the back mold member where each member of a class of backmold members is shaped similarly. These points may be found at locationsalong gasket 510, oblique to the steep and flat axes of the moldmembers. In a preferred embodiment, these points are at about 45 degreeangles to the steep and flat axes of the mold members. By using discreteprojections 511 to space the mold members at these points, an individualgasket could be used with a variety of mold sets. Therefore, the numberof gaskets that would have to be kept in stock may be greatly reduced.

In addition, gasket 510 may include a recession 518 for receiving a lensforming composition. Lip 520 may be pulled back in order to allow a lensforming composition to be introduced into the cavity. Vent ports 516 maybe incorporated to facilitate the escape of air from the mold cavity asa lens forming composition is introduced.

Gasket 510 may also include a projection 540. Projection 540 may extendfrom the side of the gasket toward the interior of the mold cavity whena first and second mold are assembled with the gasket. The projection ispositioned such that a groove is formed in a plastic lens formed usingthe mold assembly. The groove may be positioned near an outer surface ofthe formed lens. In this manner the groove is formed near the interfacebetween the mold members and the formed lens. FIG. 14 depicts a sideview of an lens 550 disposed between two mold members 526 after curingand the removal of the gasket. A variety of indentations/grooves may beseen along the outer surface of the lens caused by the variousprojections from the gasket. Grooves 544 may be caused by theprojections 511 of a gasket used to space the mold members at theappropriate distance. Groove 546 may be caused by the projection 540.The groove is positioned at the interface of the mold members and theformed lens. While depicted as near the interface of the upper moldmember, it should be understood that the groove may also be positionedat the interface between the lower mold member and the formed lens. Inone embodiment, the fill port 538 (see FIGS. 12 and 13) may produce agroove near the interface of the upper mold member and the formed lens.The projection 511 may therefore be positioned at the interface betweenthe lower mold member and the formed lens. In this manner, two groovesmay be created at the interfaces between the formed lens and each of themold members.

After the gasket is been removed, the molds may adhere to the formedlens. In some instances a sharp object may be inserted between the moldmembers and the formed lens to separate the formed lens from the moldmembers. The groove 546 may facilitate the separation of the moldmembers from the formed lens by allowing the insertion of a sharp objectto pry the molds away from the formed lens.

FIGS. 12 and 13 present an isometric view and a top view, respectively,of an improved gasket. Gasket 530 may be composed of similar materialsas gasket 510. Like gasket 510, gasket 530 is preferably annular, butmay be take a variety of shapes. In addition, gasket 530 may incorporateprojections 531 in a manner similar to the projections 511 shown in FIG.9. Alternatively, gasket 530 may include a raised lip along interiorsurface 532 or another method of spacing mold members that isconventional in the art.

Gasket 530 preferably includes a fill port 538 for receiving a lensforming composition while gasket 530 is fully engaged to a mold set.Fill port 538 preferably extends from interior surface 532 of gasket 530to an exterior surface 534 of gasket 530. Consequently, gasket 530 neednot be partially disengaged from a mold member of a mold set in order toreceive a lens forming composition. In order to introduce a lens formingcomposition into the mold cavity defined by a conventional mold/gasketassembly the gasket must be at least partially disengaged from the moldmembers. During the process of filling the mold cavity, lens formingcomposition may drip onto the backside of a mold member. Lens formingcomposition on the backside of a mold member may cause activating lightused to cure the lens to become locally focused, and may cause opticaldistortions in the final product. Because fill port 538 allows lensforming composition to be introduced into a mold cavity while gasket 530is fully engaged to a mold set, gasket 530 preferably avoids thisproblem. In addition, fill port 538 may be of sufficient size to allowair to escape during the introduction of a lens forming composition intoa mold cavity; however, gasket 530 may also incorporate vent ports 536to facilitate the escape of air.

A method for making a plastic eyeglass lenses using either gasket 510 or530 is presented. The method preferably includes engaging gasket 510with a first mold set for forming a first lens of a first power. Thefirst mold set preferably contains at least a front mold member 526 aand a back mold member 526 b. A mold cavity for retaining a lens formingcomposition may be at least partially defined by mold members 526 a and526 b and gasket 510. Gasket 510 is preferably characterized by at leastfour discrete projections 511 arranged on interior surface 512 forspacing the mold members. Engaging gasket 510 with the mold setpreferably includes positioning the mold members such that each of theprojections 511 forms an oblique angle with the steep and flat axis ofthe back mold member 526 b. In a preferred embodiment, this angle isabout 45 degrees. The method preferably further includes introducing alens forming composition into mold cavity 528 and curing the lensforming composition. Curing may include exposing the composition toactivating light and/or thermal radiation. After the lens is cured, thefirst mold set may be removed from the gasket and the gasket may then beengaged with a second mold set for forming a second lens of a secondpower. When using the gasket 530. the method further includesintroducing a lens forming composition through fill port 538, whereinthe first and second mold members remain fully engaged with the gasketduring the introduction of the lens forming composition. The lensforming composition may then be cured by use of activating light and/orthermal radiation.

After curing of the lens in lens curing unit 30, the lens may bede-molded and post-cured in the post-cure unit 40. Post-cure unit 40 ispreferably configured to apply light, heat or a combination of light andheat to the lens. As shown in FIG. 15, post-cure unit 40 may include alight source 414, a lens drawer assembly 416, and a heat source 418.Lens drawer assembly 416 preferably includes a lens holder 420, morepreferably at least two lens holders 420. Lens drawer assembly 416 ispreferably slidingly mounted on a guide. Preferably, lens drawerassembly 416 is made from a ceramic material. Cured lenses may be placedin lens holders 420 while the lens drawer assembly 416 is in the openposition (i.e., when the door extends from the front of post-cure unit40 ). After the lenses have been loaded into lens holders 420 the doormay be slid into a closed position, with the lenses directly under lightsource 414 and above heat source 418.

As shown in FIG. 15, it is preferred that the light source 414 includesa plurality of light generating devices or lamps 440. Preferably, lamps440 may be oriented above each of the lens holders when the lens drawerassembly is closed. The lamps 440, preferably, generate activatinglight. The lamps 440 may be supported by and electrically connected tosuitable fixtures 442. The fixtures may be at least partially reflectiveand concave in shape to direct light from the lamps 440 toward the lensholders. The lamps may generate either ultraviolet light, actinic light,visible light, and/or infrared light. The choice of lamps is preferablybased on the monomers used in the lens forming composition. In oneembodiment, the activating light may be generated from a fluorescentlamp. The fluorescent lamp preferably has a strong emission spectra fromabout 200 nm to about 800 nm, more preferably between about 200 nm toabout 400 nm. A fluorescent lamp emitting activating light with thedescribed wavelengths is commercially available from Voltarc as modelSNEUV RPR 4190. In another embodiment, the lamp may generate ultravioletlight.

In one embodiment, the activating light source may be turned on and offquickly between exposures. A ballast may be used for this function. Theballast may be positioned beneath the post-cure unit. Alternatively, aballast and transformer system, as depicted in FIG. 7 and describedabove may be used to control the activating light source.

Heat source 418 may be configured to heat the interior of the post-cureunit. Preferably, heat source 418 is a resistive heater. Heat source 418may be made up of one or two resistive heaters. The temperature of heatsource 418 may be thermostatically controlled. By heating the interiorof the post-cure unit the lenses which are placed in post-cure unit 40may be heated to complete curing of the lens forming material. Post-cureunit 40 may also include a fan to circulate air within the unit. Thecirculation of air within the unit may help maintain a relativelyuniform temperature within the unit. The fan may also be used to coolthe temperature of post-cure unit 40 after completion of the post cureprocess.

In an embodiment, a lens cured by exposure to activating light may befurther processed by conductive heating. The use of a conductive heatingpost-cure procedure is described in detail in U.S. Pat. No. 5,928,575 toBuazza which is incorporated by reference.

In another embodiment, the edges of a lens may be treated to cure orremove incompletely cured lens forming material (see above description)before a post-cure heat is applied. Techniques for further curing ofincompletely cured lens forming material are described in U.S. Pat. No.5,976,423 to Buazza which is incorporated by reference.

In another embodiment, a lens may be tinted after receiving conductiveheat postcure treatment in a mold cavity. During tinting of the lens,the lens is preferably immersed in a dye solution.

The operation of the lens curing system may be controlled by amicroprocessor based controller 50 (FIG. 1). Controller 50 preferablycontrols the operation of coating unit 20, lens curing unit 30, andpost-cure unit 40. Controller 50 may be configured to substantiallysimultaneously control each of these units. In addition, the controllermay include a display 52 and an input device 54. The display and inputdevice may be configured to exchange information with an operator.

Controller 50 preferably controls a number of operations related to theprocess of forming a plastic lens. Many of the operations used to make aplastic lens (e.g., coating, curing and post-cure operations) arepreferably performed under a predetermined set of conditions based onthe prescription and type of lens being formed (e.g.,ultraviolet/visible light absorbing, photochromic, colored, etc.).Controller 50 is preferably programmed to control a number of theseoperations, thus relieving the operator from having to continuallymonitor the apparatus.

In some embodiments, the lens or mold members may be coated with avariety of coatings (e.g., a scratch resistant or tinted coating). Theapplication of these coatings may require specific conditions dependingon the type of coating to be applied. Controller 50 is preferablyconfigured to produce these conditions in response to input from theoperator.

When a spin coating unit is used, controller 50 may be configured tocontrol the rotation of the lens or mold member during the coatingprocess. Controller 50 is preferably electronically coupled to the motorof the spin coating unit. The controller may send electronic signals tothe motor to turn the motor on and/or off. In a typical coating processthe rate at which the mold or lens is rotated is preferably controlledto achieve a uniform and defect free coating. The controller ispreferably configured to control the rate of rotation of the mold orlens during a curing process. For example, when a coating material isbeing applied, the mold or lens is preferably spun at relatively highrotational rates (e.g., about 900 to about 950 RPM). When the coatingmaterial is being cured, however, a much slower rotational rate ispreferably used (e.g., about 200 RPM). The controller is preferablyconfigured to adjust the rotational rate of the lens or mold dependingon the process step being performed.

The controller is also preferably configured to control the operation oflamps 24. The lamps are preferably turned on and off at the appropriatetimes during a coating procedure. For example, during the application ofthe coating material activating lights are typically not used, thus thecontroller may be configured to keep the lamps off during this process.During the curing process, activating light may be used to initiate thecuring of the coating material. The controller is preferably configuredto turn the lamps on and to control the amount of time the lamps remainon during a curing of the coating material. The controller may also beconfigured to create light pulses to affect curing of the coatingmaterial. Both the length and frequency of the light pulses may becontrolled by the controller.

The controller is also preferably configured to control operation of thelens-curing unit. The controller may perform some and/or all of a numberof functions during the lens curing process, including, but not limitedto: (i) measuring the ambient room temperature; (ii) determining thedose of light (or initial dose of light in pulsed curing applications)required to cure the lens forming composition, based on the ambient roomtemperature; (iii) applying the activating light with an intensity andduration sufficient to equal the determined dose; (iv) measuring thecomposition's temperature response during and subsequent to theapplication of the dose of light; (v) calculating the dose required forthe next application of activating light (in pulsed curingapplications); (vi) applying the activating light with an intensity andduration sufficient to equal the determined second dose; (vii)determining when the curing process is complete by monitoring thetemperature response of the lens forming composition during theapplication of activating light; (viii) turning the upper and lowerlight sources on and off independently; (ix) monitoring the lamptemperature, and controlling the temperature of the lamps by activatingcooling fans proximate the lamps; and (x) turning the fans on/off orcontrolling the flow rate of an air stream produced by a fan to controlthe composition temperature. Herein, “dose” refers to the amount oflight energy applied to an object, the energy of the incident lightbeing determined by the intensity and duration of the light. Acontroller that is configured to alter the dose activating light appliedto a lens forming composition in response to the temperature of lensforming composition is described in U.S. Pat. No. 5,989,462 to Buazza etal. which is incorporated by reference.

In an embodiment, a shutter system may be used to control theapplication of activating light rays to the lens forming material. Theshutter system preferably includes air-actuated shutter plates that maybe inserted into the curing chamber to prevent activating light fromreaching the lens forming material. The shutter system may be coupled tothe controller, which may actuate an air cylinder to cause the shutterplates to be inserted or extracted from the curing chamber. Thecontroller preferably allows the insertion and extraction of the shutterplates at specified time intervals. The controller may receive signalsfrom temperature sensors allowing the time intervals in which theshutters are inserted and/or extracted to be adjusted as a function of atemperature of the lens forming composition and/or the molds. Thetemperature sensor may be located at numerous positions proximate themold cavity and/or casting chamber.

In some embodiments, the lens may require a post-curing process. Thepost-cure process may require specific conditions depending on the typeof lens being formed. The controller is preferably configured to producethese conditions in response to input from the operator.

The controller is preferably configured to control the operation oflamps in the post-cure unit. The lamps are preferably turned on and offat the appropriate times during the post-cure procedure. For example, insome post-cure operations the lights may not be required, thus thecontroller would keep the lights off during this process. During otherprocesses, the lights may be used to complete the curing of the lens.The controller is preferably configured to turn the lights on and tocontrol the amount of time the lights remain on during a post-cureprocedure. The controller may also be configured to create light pulsesduring the post-cure procedure. Both the length and frequency of thelight pulses may be controlled by the controller.

The controller is preferably configured to control operation of theheating device 418 during the post-cure operation. Heating device 418 ispreferably turned on and off to maintain a predetermined temperaturewithin the post-cure unit. Alternatively, when a resistive heater isused, the current flow through the heating element may be altered tocontrol the temperature within the post-cure unit. Preferably both theapplication of light and heat are controlled by the controller. Theoperation of fans, coupled to the post-cure unit, is also preferablycontrolled by the controller. The fans may be operated by the controllerto circulate air within or into/out of the post-cure unit.

Additionally, the controller may provide system diagnostics to determineif the system is operating properly. The controller may notify the userwhen routine maintenance is due or when a system error is detected. Thesystem monitors the following conditions to warn the user when themachine has malfunctioned, requires standard maintenance, or is driftingout of its suggested operating envelope: I²C network errors; linevoltage; top rack light intensity; bottom rack light intensity;post-cure rack light intensity; top activating light ballast current;bottom activating light ballast current; post-cure activating lightballast current; germicidal light ballast current; post-cure heatercurrent; top activating light filament heat transformer current; bottomactivating light filament heat transformer current; germicidal lightfilament heat transformer current; the number of times the topactivating light is turned on; the number of times the bottom activatinglight is turned on; the number of times the post-cure activating lightis turned on; the number of times the germicidal light is turned on; topactivating light on time; bottom activating light on time; post cureactivating light on time; germicidal light on time; top lamptemperature; bottom lamp temperature; spin board temperature; post-curetemperature.

For example, the controller may monitor the current passing throughlamps of the coating, lens curing, or post-cure unit to determine if thelamps are operating properly. The controller may keep track of thenumber of hours that the lamps have been used. When a lamp has been usedfor a predetermined number of hours a message may be transmitted to anoperator to inform the operator that the lamps may require changing. Thecontroller may also monitor the intensity of light produced by the lamp.A photodiode may be placed proximate the lamps to determine theintensity of light being produced by the lamp. If the intensity of lightfalls outside a predetermined range, the current applied to the lamp maybe adjusted to alter the intensity of light produced (either increasedto increase the intensity; or decreased to decrease the intensity).Alternatively, the controller may transmit a message informing theoperator that a lamp needs to be changed when the intensity of lightproduced by the lamp drops below a predetermined value.

When the machine encounters an error in these areas, the following errormessages may be displayed:

post cure temperature The temperature of your post cure is out of itssuggested operating range. If the lens drawer is closed, the unit hashad sufficient warm-up time, and the problem continues after a systemrestart, your machine may need service.

light intensity Your—light source output has dropped below itsrecommended range. If the problem continues after a system restart, youmay need to replace your—lamps.

lamp power Your—lamps are not functioning properly. If the problemcontinues after a system restart, you may need to replace your—lamps.

filament heat power Your—lamps are not functioning properly. If theproblem continues after a system restart, you may need to replaceyour—lamps.

lamp on time Your—lamps have exceeded their expected life. Pleasereplace your—lamps.

PC heaters The heaters in your post cure unit are not functioningproperly. If the problem continues after a system restart, your machinemay need service

The controller may also manage an interlock system for safety and energyconservation purposes. If the lens drawer assembly from the coating orpost-cure units are open the controller is preferably configured toprevent the lamps from turning on. This may prevent the operator frominadvertently becoming exposed to the light from the lamps. Lamps 24 forthe coating unit 20 are preferably positioned on cover 22 (See FIG. 1).In order to prevent inadvertent exposure of the operator to light fromlamps 24 a switch is preferably built into the cover, as describedabove. The controller is preferably configured to prevent the lamps 24from turning on when the cover is open. The controller may alsoautomatically turn lamps 24 off if the cover is opened when the lensesare on. Additionally, the controller may conserve energy by keeping fansand other cooling devices off when the lamps are off.

The controller may display a number of messages indicating problems thatprevent further operation of the lens forming apparatus. Process tipsappear in the appropriate location on the display (over a button whenrelated to that function, at the top and flashing when important, etc.).The controller uses the following list of tips to instruct the userduring machine use. The list is in order of priority (i.e. the tip atthe top of the list is displayed if both it and the second item need tobe displayed simultaneously).

WARNING JOBS RUNNING, CONFIRM PURGE

WARNING JOBS RUNNING, CONFIRM RERUN

ROTATE ENCODER TO CONFIRM PURGE

NOT ALLOWED WHILE JOBS RUNNING

MOVE CAVITY TO POST-CURE & PRESS THE KEY CLOSE LID

PRESS & HOLD TO RERUN POST-CURE PROCESS

PRESS & HOLD TO RERUN CURE PROCESS

PRESS & HOLD TO RERUN ANNEAL PROCESS

PRESS & HOLD TO CANCEL

PRESS & HOLD TO RERUN COAT PROCESS

PRESS THE CURE KEY TO START JOB

MUST WAIT FOR POST-CURE TO COMPLETE

MUST WAIT FOR POST-CURE TO START

MUST SPIN LEFT AND RIGHT BOWLS

NO JOBS CURRENTLY IN MEMORY

ROTATE ENCODER TO SELECT JOB

NO CURED JOBS AVAILABLE TO POST-CURE

NO JOBS READY TO ANNEAL

LEFT MOLD DOES NOT EXIST, RE-ENTER RX

RIGHT MOLD DOES NOT EXIST, RE-ENTER RX

MOLDS NOT IN KIT, ACCEPT OR RE-ENTER RX

ROTATE ENCODER TO SELECT SAVE OR DISCARD

RESS ENCODER WHEN READY

. . . PLEASE WAIT WHILE COMPUTING

ANNEAL COMPLETE

COAT COMPLETE

POST-CURE COMPLETE, DEMOLD & ANNEAL

MOLDS DO NOT EXIST, RE-ENTER RX

RIGHT MOLD NOT IN KIT, ACCEPT|RE-ENTER

LEFT MOLD NOT IN KIT, ACCEPT|RE-ENTER

THERE ARE NO STORED Rx's TO EDIT

THERE ARE NO JOBS TO PURGE/RERUN

THERE ARE NO STORED JOBS TO VIEW

THERE ARE NO STORED JOBS TO EDIT

The controller may also be configured to interact with the operator. Thecontroller preferably includes an input device 54 and a display screen52. The input device may be a keyboard (e.g., a full computer keyboardor a modified keyboard), a light sensitive pad, a touch sensitive pad,or similar input device. A number the parameters controlled by thecontroller may be dependent on the input of the operator. In the initialset up of the apparatus, the controller may allow the operator to inputthe type of lens being formed. This information may include type of lens(clear, ultraviolet absorbing, photochromic, colored, etc.),prescription, and type of coatings (e.g., scratch resistant or tint).

Based on this information the controller is preferably configured totransmit information back to the operator. The operator may beinstructed to select mold members for the mold assembly. The moldmembers may be coded such that the controller may indicate to theoperator which molds to select by transmitting the code for each moldmember. The controller may also determine the type of gasket required toproperly seal the mold members together. Like the mold members, thegaskets may also be coded to make the selection of the appropriategasket easier.

The lens forming compositions may also be coded. For the production ofcertain kinds of lenses a specific lens forming composition may berequired. The controller may be configured to determine the specificcomposition required and transmit the code for that composition to theoperator. The controller may also signal to the operator when certainoperations need to be performed or when a particular operation iscompleted (e.g., when to place the mold assembly in the lens curingunit, when to remove the mold assembly, when to transfer the moldassembly, etc.).

The controller may also display Help functions to instruct the user onmachine use and give general process guidance. The following paragraphsare examples of some of the help files that may be available to anoperator:

1) Navigation and Data Entry

The information entry knob is used for most data selection and entry.Rotating the knob moves the cursor in menus and scrolls through choiceson data entry screens.

Pressing the knob down enters the selection. Prompts at the top of thescreen help the user through the process. The arrow keys allow forcorrection of previously entered data and can be used as an alternativeto the data entry knob during navigation.

The menu key returns the user to the previous menu.

The help key gives general process help and also shows machinemalfunctions when there is a problem with the system. When an error ispresent, the user will be given information about any errors andsuggested courses of action to remedy them.

2) Screen Descriptions

NEW Rx Prescription information is entered in this screen. Theavailability of molds is displayed on this screen in real time. Moldsthat are available have a checkmark next to them. Molds that can beadded to your kit are displayed with a box next to them. Powers that areout of the range of the machine will produce dashes in the area wherethe mold information is normally shown. When all prescriptioninformation is entered the data entry knob is pressed and the job issaved in memory. The view screen displays the data for cavity creation.If the data was entered in plus cylinder format, it will be transposedand shown in minus cylinder form. If you need to see the data as it wasinput, it is available in the EDIT Rx screen in both plus and minuscylinder forms.

VIEW and EDIT Allow the user to see and modify jobs that are in memory.Once the view or edit selection is made on the main menu, the user canscroll through all jobs that have been saved. When using edit, pressingthe data entry knob will move the cursor into an edit screen where thedisplayed job's prescription can be modified. In the view menu, pressingthe knob will put the user at the main menu.

PURGE/RERUN JOB Allows the user to delete and rerun jobs if necessary.When a single lens of a pair needs to be rerun, edit job can be used tochange the job type to left or right only after rerun is selected forthat job. Purge all jobs clears all jobs from the memory. If you wouldlike to start your job numbering back at zero, this feature is used.

INSTRUMENT STATUS Shows the current status of individual sections of themachine-spin speeds, current being delivered to a device, network errorsetc. These screens are useful when diagnosing errors. The system'sserial numbers and software version numbers are also in the statusscreens.

ADVANCED The advanced menu contains all user adjustable settings,program upload options, and mold kit selections. This menu is passwordprotected to minimize the risk that changes will be made by accident.When password is displayed, pressing the data entry knob lets the userenter a password by rotating the data entry knob. Press the knob whenthe proper password is dialed in. Incorrect passwords will return theuser to the password screen. The proper password will take the user tothe advanced menu which functions like the main menu. Within thesemenus, when the desired field is highlighted, the data entry knob ispressed and parentheses appear around the field indicating that it ischangeable by rotating the data entry knob. When the proper value isselected, pressing the knob again removes the parentheses and sets thefield to the value selected. In the date and time setting screen,changes will not be saved until the save settings field is highlightedand the data entry knob is pressed. The kit menu allows the user toselect the available mold package and power range.

3) Running a Job

Making lenses is a 3 part process. Applying a scratch resistant coatingis optional and is covered at the end of this section.

When the user enters a prescription and saves the job, the view screendisplays the data required to retrieve the molds and gasket necessaryfor each lens. The system is designed for minus cylinder formatprescriptions. If the Rx information is entered in plus cylinder format,it will be transposed and returned in minus cylinder form. The cavitymust be assembled based on the view screen data (the axis will be 90°different from the plus cylinder input). The original prescription canbe viewed at the Edit Rx screen along with its transposed returninformation.

Before assembling a cavity, the molds and gasket must be thoroughlycleaned. Any contaminants on the molds or gasket may be included in thefinished lens rendering it undispensable. Spin clean the casting side ofeach mold with IPA and acetone. Assemble the cavity next, ensuring thatthe axis is set properly. Fill the cavity with the appropriate monomer.A filled cavity should not be exposed to room light for more than 3minutes. High ambient light levels caused by windows or high intensityroom lighting can significantly shorten the allowable room lightexposure time.

CURING Press the cure button to initiate a curing cycle. Rotating thedata entry knob will allow the user to select the job to be run. Thenecessary filters for the cycle are displayed with the job number. Whenthe correct job is displayed, press the cure key. The area over the keyinstructs you to put in the pair or the left or right lens only. Ensurethat the left and right lenses are always on the proper side of thechamber. Put the cavity in the initial curing drawer and press the curebutton. When the initial cure is done, transfer the cavity or cavitiesto the front part of the post cure drawer and press the post cure key.If the job was split because of power differences in the left and rightlenses, the area over the cure button will instruct the user to insertthe second cavity in the initial cure drawer and press the cure keyagain (the first cavity should be in the post cure when performing theinitial curing step on the second cavity). When prompted, move thecavity to the post cure section and press the post cure button again.

POST CURING The front openings in the post cure oven drawer are used topost cure the cavities. When the post cure cycle is over, press the postcure key, remove the cavities from the post cure chamber, and allow themto cool for 1 to 2 minutes. After the cooling period, remove the gasketand separate one mold from each assembly with the demolding tool. Thetool is inserted in the gap created by the tab on the gasket and themold is gently pried off the assembly. Place the remaining lens and moldin the Q-Soak container to separate the mold from the lens. Clean thelenses and proceed to the annealing step.

ANNEALING If more than one job is available for annealing, the user canchoose which job they would like to anneal by rotating the data entryknob when the area over the anneal button displays a job number. Pressthe anneal button when the proper job is displayed. The cleaned lens isplaced over the rear openings of the post cure chamber drawer. Press theanneal key when prompted at the end of the annealing cycle.

COATING Scratch coating is optional and is applied in the spin bowls ofthe main chamber. The timed buttons by the spin bowls initiate the coatcuring cycle.

When the front molds are cleaned and coated, the hood is closed and a 90second curing cycle is started for the coatings. When the cycle iscomplete, the light turns off, the motors stop, and the controllersignals the user that the molds are ready. The cavity is assembled inthe normal fashion and the lens monomer is dispensed into the cavity.

Lens coating is also available and is applied to the finished lens afterthe annealing step is complete.

4) Tinting Tips

After edging, lenses may be tinted by conventional means. As with manymodem lens materials, tinting results may be improved with slightlymodified handling procedures. First, when mounting the lenses in the dyeholders, do not use spring-type holders or apply excessive pressure tothe lenses. Lenses become somewhat flexible at dye tank temperatures andmay bend. Faster and more uniform dye absorption will be achieved if thelenses are agitated in a slow back and forth motion while in the dyetank.

In some embodiments, the controller may be a computer system. A computersystem may include a memory medium on which computer programs configuredto perform the above described operations of the controller are stored.The term “memory medium” is intended to include an installation medium,e.g., a CD-ROM, or floppy disks, a computer system memory such as DRAM,SRAM, EDO RAM, Rambus RAM, etc., or a non-volatile memory such as amagnetic media, e.g., a hard drive, or optical storage. The memorymedium may comprise other types of memory as well, or combinationsthereof. In addition, the memory medium may be located in a firstcomputer in which the programs are executed, or may be located in asecond different computer that connects to the first computer over anetwork. In the latter instance, the second computer provides theprogram instructions to the first computer for execution. Also, thecomputer system may take various forms, including a personal computersystem, mainframe computer system, workstation, network appliance,Internet appliance, personal digital assistant (PDA), television systemor other device. In general, the term “computer system” can be broadlydefined to encompass any device having a processor which executesinstructions from a memory medium.

The memory medium preferably stores a software program for controllingthe operation of a lens forming apparatus. The software program may beimplemented in any of various ways, including procedure-basedtechniques, component-based techniques, and/or object-orientedtechniques, among others. For example, the software program may beimplemented using ActiveX controls, C++ objects, JavaBeans, MicrosoftFoundation Classes (MFC), or other technologies or methodologies, asdesired. A CPU, such as the host CPU, executing code and data from thememory medium comprises a means for creating and executing the softwareprogram according to the methods or flowcharts described below.

Various embodiments further include receiving or storing instructionsand/or data implemented in accordance with the foregoing descriptionupon a carrier medium. Suitable carrier media include memory media orstorage media such as magnetic or optical media, e.g., disk or CD-ROM,as well as signals such as electrical, electromagnetic, or digitalsignals, conveyed via a communication medium such as networks and/or awireless link.

LENS FORMING COMPOSITIONS

The lens forming material may include any suitable liquid monomer ormonomer mixture and any suitable photosensitive initiator. As usedherein “monomer” is taken to mean any compound capable of undergoing apolymerization reaction. Monomers may include non-polymerized materialor partially polymerized material. When partially polymerized materialis used as a monomer, the partially polymerized material preferablycontains functional groups capable of undergoing further reaction toform a new polymer. The lens forming material preferably includes aphotoinitiator that interacts with activating light. In one embodiment,the photoinitiator absorbs ultraviolet light having a wavelength in therange of 300 to 400 nm. In another embodiment, the photoinitiatorabsorbs actinic light having a wavelength in the range of about 380 nmto 490 nm. The liquid lens forming material is preferably filtered forquality control and placed in the lens molding cavity 382 by pulling theannular gasket 380 away from one of the opposed mold members 378 andinjecting the liquid lens forming material into the lens molding cavity382 (See FIG. 11). Once the lens molding cavity 382 is filled with suchmaterial, the annular gasket 380 is preferably replaced into its sealingrelation with the opposed mold members 378.

Those skilled in the art will recognize that once the cured lens isremoved from the lens molding cavity 382 by disassembling the opposedmold members 378, the lens may be further processed in a conventionalmanner, such as by grinding its peripheral edge.

A polymerizable lens forming composition includes an aromatic-containingbis(allyl carbonate)-functional monomer and at least onepolyethylenic-functional monomer containing two ethylenicallyunsaturated groups selected from acrylyl or methacrylyl. In a preferredembodiment, the composition further includes a suitable photoinitiator.In other preferred embodiments, the composition may include one or morepolyethylenic-functional monomers containing three ethylenicallyunsaturated groups selected from acrylyl or methacrylyl, and a dye. Thelens forming composition may also include activating light absorbingcompounds such as ultraviolet light absorbing compounds and photochromiccompounds. Examples of these compositions are described in more detailin U.S. Pat. No. 5,989,462 to Buazza et al. which is ncorporated byreference.

In another embodiment, an ophthalmic eyeglass lens may be made from alens forming composition comprising a monomer composition and aphotoinitiator composition

The monomer composition preferably includes an aromatic containingpolyethylenic polyether functional monomer. In an embodiment, thepolyether employed is an ethylene oxide derived polyether, propyleneoxide derived polyether, or mixtures thereof. Preferably, the polyetheris an ethylene oxide derived polyether. The aromatic polyetherpolyethylenic functional monomer preferably has the general structure(V), depicted below where each R₂ is a polymerizable unsaturated group,m and n are independently 1 or 2, and the average values of j and k areeach independently in the range of from about 1 to about 20. Commonpolymerizable unsaturated groups include vinyl, allyl, allyl carbonate,methacrylyl, acrylyl, methacrylate, and acrylate.

R₂—[CH₂—(CH₂)_(m)—-O]_(j)—A₁—[O—(CH₂)_(n)—CH₂]_(k)—R₂

A₁ is the divalent radical derived from a dihydroxy aromatic-containingmaterial. A subclass of the divalent radical A₁ which is of particularusefulness is represented by formula (II):

in which each R₁ is independently alkyl containing from 1 to about 4carbon atoms, phenyl, or halo; the average value of each (a) isindependently in the range of from 0 to 4; each Q is independently oxy,sulfonyl, alkanediyl having from 2 to about 4 carbon atoms, oralkylidene having from 1 to about 4 carbon atoms; and the average valueof n is in the range of from 0 to about 3. Preferably Q ismethylethylidene, viz., isopropylidene.

Preferably the value of n is zero, in which case A₁ is represented byformula (III):

in which each R₁, each a, and Q are as discussed with respect to FormulaII. Preferably the two free bonds are both in the ortho or parapositions. The para positions are especially preferred.

In an embodiment, when para, para-bisphenols are chain extended withethylene oxide, the central portion of the aromatic containingpolyethylenic polyether functional monomer may be represented by theformula:

where each R₁, each a, and Q are as discussed with respect to FormulaII, and the average values of j and k are each independently in therange of from about 1 to about 20.

In another embodiment, the polyethylenic functional monomer is anaromatic polyether polyethylenic functional monomer containing at leastone group selected from acrylyl or methacrylyl. Preferably the aromaticpolyether polyethylenic functional monomer containing at least one groupselected from acrylate and methacrylate has the general structure (VI),depicted below where R₀ is hydrogen or methyl, where each R₁, each a,and Q are as discussed with respect to Formula II, where the values of jand k are each independently in the range of from about 1 to about 20,and where R₂ is a polymerizable unsaturated group (e.g., vinyl, allyl,allyl carbonate, methacrylyl, acrylyl, methacrylate, or acrylate).

In one embodiment, the aromatic containing polyether polyethylenicfunctional monomer is preferably an ethoxylated bisphenol Adi(meth)acrylate. Ethoxylated bisphenol A di(meth)acrylates have thegeneral structure depicted below where each R₀ is independently hydrogenor methyl, each R₁, each a, and Q are as discussed with respect toFormula II, and the values of j and k are each independently in therange of from about 1 to about 20.

Preferred ethoxylated bisphenol A dimethacrylates include ethoxylated 2bisphenol A diacrylate (where j+k=2, and R₀ is H), ethoxylated 2bisphenol A dimethacrylate (where j+k=2, and R₀ is Me), ethoxylated 3bisphenol A diacrylate (where j+k=3, and R₀ is H), ethoxylated 4bisphenol A diacrylate (where j+k=4, and R₀ is H), ethoxylated 4bisphenol A dimethacrylate (where j+k=4, and R₀ is Me), thoxylated 6bisphenol A dimethacrylate (where j+k=6, and R₀ is Me), ethoxylated 8bisphenol A dimethacrylate (where j+k=8, and R₀ is Me), ethoxylated 10bisphenol A diacrylate (where j+k=10, and R₀ is H), ethoxylated 10bisphenol A dimethacrylate (where j+k=10, and R₀ is Me), ethoxylated 30bisphenol A diacrylate (where j+k=30, and R₀ is H), ethoxylated 30bisphenol A dimethacrylate (where j+k=30, and R₀ is Me). These compoundsare commercially available from Sartomer Company under the trade namesPRO-631, SR-348, SR-349, SR-601, CD-540, CD-541, CD-542, SR-602, SR-480,SR-9038, and SR-9036 respectively. Other ethoxylated bisphenol Adimethacrylates include ethoxylated 3 bisphenol A dimethacrylate (wherej+k=3, and R₀ is Me), ethoxylated 6 bisphenol A diacrylate (wherej+k=30, and R₀ is H), and ethoxylated 8 bisphenol A diacrylate (wherej+k=30, and R₀ is H). In all of the above described compounds Q isC(CH₃)₂.

The monomer composition preferably may also include a polyethylenicfunctional monomer. Polyethylenic functional monomers are defined hereinas organic molecules which include two or more polymerizable unsaturatedgroups. Common polymerizable unsaturated groups include vinyl, allyl,allyl carbonate, methacrylyl, acrylyl, methacrylate, and acrylate.Preferably, the polyethylenic functional monomers have the generalformula (VII) or (VIII) depicted below, where each R₀ is independentlyhydrogen, halo, or a C₁-C₄ alkyl group and where A₁ is as describedabove. It should be understood that while general structures (VII) and(VIII) are depicted as having only two polymerizable unsaturated groups,polyethylenic functional monomers having three (e.g.,tri(meth)acrylates), four (e.g., tetra(meth)acrylates), five (e.g.,penta(meth)acrylates), six (e.g., hexa(meth)acrylates) or more groupsmay be used.

Preferred polyethylenic functional monomers which may be combined withan aromatic containing polyethylenic polyether functional monomer toform the monomer composition include, but are not limited to,ethoxylated 2 bisphenol A dimethacrylate,tris(2-hydroxyethyl)isocyanurate triacrylate, ethoxylated 10 bisphenol Adimethacrylate, ethoxylated 4 bisphenol A dimethacrylate,dipentaerythritol pentaacrylate, 1,6-hexanediol dimethacrylate,isobornyl acrylate, pentaerythritol triacrylate, ethoxylated 6trimethylolpropane triacrylate, and bisphenol A bis allyl carbonate.

According to one embodiment, the liquid lens forming compositionincludes ethoxylated 4 bisphenol A dimethacrylate. Ethoxylated 4bisphenol A dimethacrylate monomer, when cured to form an eyeglass lens,typically produces lenses that have a higher index of refraction thancomparable lenses produced using DEG-BAC. Lenses formed from such amid-index lens forming composition which includes ethoxylated 4bisphenol A dimethacrylate may have an index of refraction of about 1.56compared to the non-ethoxylated monomer compositions which tend to havean index of refraction of about 1.51. A lens made from a higher index ofrefraction polymer may be thinner than a lens made from a lower index ofrefraction polymer because the differences in the radii of curvaturebetween the front and back surface of the lens do not have to be asgreat to produce a lens of a desired focal power. Lenses formed from alens forming composition which includes ethoxylated 4 bisphenol Adimethacrylate may also be more rigid than lenses formed fromnon-ethoxylated monomer based compositions.

The monomer composition may include additional monomers, which, whencombined with ethoxylated 4 bisphenol A dimethacrylate, may modify theproperties of the formed eyeglass lens and/or the lens formingcomposition. Tris(2-hydroxyethyl)isocyanurate triacrylate, availablefrom Sartomer under the trade name SR-368, is a triacrylate monomer thatmay be included in the composition to provide improved clarity, hightemperature rigidity, and impact resistance properties to the finishedlens. Ethoxylated 10 bisphenol A dimethacrylate, available from Sartomerunder the trade name SR-480, is a diacrylate monomer that may beincluded in the composition to provide impact resistance properties tothe finished lens. Ethoxylated 2 bisphenol A dimethacrylate, availablefrom Sartomer under the trade name SR-348, is a diacrylate monomer thatmay be included in the composition to provide tintability properties tothe finished lens. Dipentaerythritol pentaacrylate, available fromSartomer under the trade name SR-399, is a pentaacrylate monomer thatmay be included in the composition to provide abrasion resistanceproperties to the finished lens. 1,6-hexanediol dimethacrylate,available from Sartomer under the trade name SR-239, is a diacrylatemonomer that may be included in the composition to reduce the viscosityof the lens forming composition. Isobomyl acrylate, available fromSartomer under the trade name SR-506, is an acrylate monomer that may beincluded in the composition to reduce the viscosity of the lens formingcomposition and enhance tinting characteristics. Bisphenol A bis allylcarbonate may be included in the composition to control the rate ofreaction during cure and also improve the shelf life of the lens formingcomposition. Pentaerythritol triacrylate, available from Sartomer underthe trade name SR-444, is a triacrylate monomer that may be included inthe composition to promote better adhesion of the lens formingcomposition to the molds during curing. Ethoxylated 6 trimethylolpropanetriacrylate, available from Sartomer under the trade name SR-454, mayalso be added.

Photoinitiators which may be used in the lens forming composition havebeen described in previous sections. In one embodiment, thephotoinitiator composition preferably includes phenylbis(2,4,6-trimethylbenzoyl) phosphine oxide (IRG-819) which iscommercially available from Ciba Additives under the trade name ofIrgacure 819. The amount of Irgacure 819 present in a lens formingcomposition preferably ranges from about 30 ppm by weight to about 2000ppm by weight. In another embodiment, the photoinitiator composition mayinclude a mixture of photoinitiator. Preferably, a mixture of Irgacure819 and 1-hydroxycyclohexylphenyl ketone, commercially available fromCiba Additives under the trade name of Irgacure 184 (IRG-184), is used.Preferably, the total amount of photoinitiators in the lens formingcomposition ranges from about 50 ppm to about 1000 ppm.

In another embodiment, an ophthalmic eyeglass lens may be made from lensforming composition comprising a monomer composition, a photoinitiatorcomposition, and a co-initiator composition. The lens formingcomposition, in liquid form, is preferably placed in a mold cavitydefined by a first mold member and a second mold member. It is believedthat activating light which is directed toward the mold members toactivate the photoinitiator composition causes the photoinitiator toform a polymer chain radical. The co-initiator may react with a fragmentor an active species of either the photoinitiator or the polymer chainradical to produce a monomer initiating species. The polymer chainradical and the monomer initiating species may react with the monomer tocause polymerization of the lens forming composition.

The monomer composition preferably includes an aromatic containingpolyethylenic polyether functional monomer having a structure as shownabove. Preferably, the polyethylenic functional monomer is an aromaticpolyether polyethylenic functional monomer containing at least one groupselected from acrylyl or methacrylyl.

More preferably, the polyethylenic functional monomer is an ethoxylatedbisphenol A di(meth)acrylate. The monomer composition may include amixture of polyethylenic functional monomers, as described above. Thephotoinitiators which may be present in the lens forming compositionhave been described above.

The lens forming composition preferably includes a co-initiatorcomposition. The co-initiator composition preferably includes amineco-initiators. Amines are defined herein as compounds of nitrogenformally derived from ammonia (NH₃) by replacement of the hydrogens ofammonia with organic substituents. Co-initiators include acrylyl amineco-initiators commercially available from Sartomer Company under thetrade names of CN-381, CN-383, CN-384, and CN-386, where theseco-initiators are monoacrylyl amines, diacrylyl amines, or mixturesthereof. Other co-initiators include ethanolamines. Examples ofethanolamines include but are not limited to N-methyldiethanolamine(NMDEA) and triethanolamine (TEA) both commercially available fromAldrich Chemicals. Aromatic amines (e.g., aniline derivatives) may alsobe used as co-initiators. Example of aromatic amines include, but arenot limited to, ethyl-4-dimethylaminobenzoate (E-4-DMAB),ethyl-2-dimethylaminobenzoate (E-2-DMAB),n-butoxyethyl-4-dimethylaminobenzoate, p-dimethylaminobenzaldehyde,N,N-dimethyl-p-toluidine, and octyl-p-(dimethylamino)benzoatecommercially available from Aldrich Chemicals or The First ChemicalGroup of Pascagoula, Miss.

Preferably, acrylated amines are included in the co-initiatorcomposition. Acrylyl amines may have the general structures depicted inFIG. 16, where R₀ is hydrogen or methyl, n and m are 1 to 20, preferably1-4, and R₁ and R₂ are independently alkyl containing from 1 to about 4carbon atoms or phenyl. Monoacrylyl amines may include at least oneacrylyl or methacrylyl group (see compounds (A) and (B) in FIG. 16).Diacrylyl amines may include two acrylyl, two methacrylyl, or a mixtureof acrylyl or methacrylyl groups (see compounds (C) and (D) in FIG. 16).Acrylyl amines are commercially available from Sartomer Company underthe trade names of CN-381, CN-383, CN-384, and CN-386, where theseco-initiators are monoacrylyl amines, diacrylyl amines, or mixturesthereof. Other acrylyl amines include dimethylaminoethyl methacrylateand dimethylaminoethyl acrylate both commercially available fromAldrich. In one embodiment, the co-initiator composition preferablyincludes a mixture of CN-384 and CN-386. Preferably, the total amount ofco-initiators in the lens forming composition ranges from about 50 ppmto about 7% by weight.

An advantage to lens forming compositions which include a co-initiatoris that less photoinitiator may be used to initiate curing of the lensforming composition. Typically, plastic lenses are formed from a lensforming composition which includes a photoinitiator and a monomer. Toimprove the hardness of the formed lenses the concentration ofphotoinitiator may be increased. Increasing the concentration ofphotoinitiator, however, may cause increased yellowing of the formedlens, as has been described previously. To offset this increase inyellowing, a permanent dye may be added to the lens forming composition.As the amount of yellowing is increased the amount of dye added may alsobe increased. Increasing the concentration of the dye may cause thelight transmissibility of the lens to decrease.

A lens forming composition that includes a co-initiator may be used toreduce the amount of photoinitiator used. To improve the hardness of theformed lenses a mixture of photoinitiator and co-initiator may be usedto initiate curing of the monomer. The above-described co-initiatorstypically do not significantly contribute to the yellowing of the formedlens. By adding co-initiators to the lens forming composition, theamount of photoinitiator may be reduced. Reducing the amount ofphotoinitiator may decrease the amount of yellowing in the formed lens.This allows the amount of dyes added to the lens forming composition tobe reduced and light transmissibility of the formed lens may be improvedwithout sacrificing the rigidity of the lens.

The lens forming composition may also include activating light absorbingcompounds. These compounds may absorb at least a portion of theactivating light which is directed toward the lens forming compositionduring curing. One example of activating light absorbing compounds arephotochromic compounds. Photochromic compounds which may be added to thelens forming composition have been previously described. Preferably, thetotal amount of photochromic compounds in the lens forming compositionranges from about 1 ppm to about 1000 ppm. Examples of photochromiccompounds which may be used in the lens forming composition include, butare not limited to Corn Yellow, Berry Red, Sea Green, Plum Red,Variacrol Yellow, Palatinate Purple, CH-94, Variacrol Blue D, OxfordBlue and CH-266. Preferably, a mixture of these compounds is used.Variacrol Yellow is a napthopyran material, commercially available fromGreat Lakes Chemical in West Lafayette, Ind. Corn Yellow and Berry Redare napthopyrans and Sea Green, Plum Red and Palatinate Purple arespironaphthoxazine materials commercially available from KeystoneAniline Corporation in Chicago, Ill. Variacrol Blue D and Oxford Blueare spironaphthoxazine materials, commercially available from GreatLakes Chemical in West Lafayette, Ind. CH-94 and CH-266 are benzopyranmaterials, commercially available from Chroma Chemicals in Dayton, Ohio.The composition of a Photochromic Dye Mixture which may be added to thelens forming composition is described in Table 1.

TABLE 1 Photochromic Dye Mixture Corn Yellow 22.3% Berry Red 19.7% SeaGreen 14.8% Plum Red 14.0% Variacrol Yellow  9.7% Palatinate Purple 7.6% CH-94  4.0% Variacrol Blue D  3.7% Oxford Blue  2.6% CH-266  1.6%

The lens forming composition may also other activating light absorbingcompounds such as UV stabilizers, UV absorbers, and dyes. UVstabilizers, such as Tinuvin 770 may be added to reduce the rate ofdegradation of the formed lens caused by exposure to ultraviolet light.UV absorbers, such as2-(2H-benzotriazol-2-yl)-4-(1,1,3,3,-tetramethylbutyl)phenol, may beadded to the composition to provide UV blocking characteristics to theformed lens. Small amounts of dyes, such as Thermoplast Blue 684 andThermoplast Red from BASF may be added to the lens forming compositionto counteract yellowing. These classes of compounds have been describedin greater detail in previous sections.

In an embodiment, a UV absorbing composition may be added to the lensforming composition. The UV absorbing composition preferably includes aphotoinitiator and a UV absorber. Photoinitiators and UV absorbers havebeen described in greater detail in previous sections. Typically, theconcentration of UV absorber in the lens forming composition required toachieve desirable UV blocking characteristics is in the range from about0.1 to about 0.25% by weight. For example,2-(2H-benzotriazol-2-yl)-4-(1,1,3,3,-tetramethylbutyl)phenol may beadded to the lens forming composition as a UV absorber at aconcentration of about 0.17%.

By mixing a photoinitiator with a UV absorbing compound the combinedconcentration of the photoinitiator and the UV absorber required toachieve the desired UV blocking characteristics in the formed lens maybe lower than the concentration of UV absorber required if used alone.For example,2-(2H-benzotriazol-2-yl)-4-(1,1,3,3,-tetramethylbutyl)phenol may beadded to the lens forming composition as a UV absorber at aconcentration of about 0.17% to achieve the desired UV blockingcharacteristics for the formed lens. Alternatively, a UV absorbingcomposition may be formed by a combination of2-(2H-benzotriazol-2-yl)-4-(1,1,3,3,-tetramethylbutyl)phenol with thephotoinitiator 2-isopropyl-thioxanthone (ITX), commercially availablefrom Aceto Chemical in Flushing, N.Y. To achieve similar UV blockingcharacteristics in the formed lens, significantly less of the UVabsorbing composition may be added to the lens forming composition,compared to the amount of UV absorber used by itself. For example,2-(2H-benzotriazol-2-yl)-4-(1,1,3,3,-tetramethylbutyl)phenol at aconcentration of about 700 ppm, with respect to the lens formingcomposition, along with 150 ppm of the photoinitiator2-isopropyl-thioxanthone (2-ITX) may be used to provide UV blockingcharacteristics. Thus, a significant reduction, (e.g., from 0.15% downto less than about 1000 ppm), in the concentration of UV absorber may beachieved, without a reduction in the UV blocking ability of thesubsequently formed lens. An advantage of lowering the amount of UVabsorbing compounds present in the lens forming composition is that thesolubility of the various components of the composition may be improved.

Tables 2-6 list some examples of mid-index lens forming compositions.The UV absorber is2-(2H-benzotriazol-2-yl)-4-(1,1,3,3,-tetramethylbutyl)phenol.

TABLE 2 Ingredient Formula 1 Formula 2 Formula 3 Formula 4 Formula 5Formula 6 Irgacure 819 694.2 ppm 486 ppm 480 ppm 382 ppm 375 ppm 414 ppmIrgacure 184 CN 384 0.962% 0.674% 0.757% 0.62% 0.61% 0.66% CN 386 0.962%0.674% 0.757% 0.62% 0.61% 0.66% SR-348 97.98% 68.65%  98.2% 81.2% 79.6%86.4% SR-368 SR-480 29.95% CD-540 SR-399 SR-239  2.0% 2.08% SR-506 CR-7317.2% 16.9% 10.0% PRO-629 Tinuvin 770 290 ppm UV Absorber 0.173%Thermoplast Blue 0.534 ppm 0.374 ppm 0.6 ppm 0.5 ppm 4.5 ppm 4.58 ppmThermoplast Red 0.019 ppm 0.0133 ppm 0.015 ppm 0.012 ppm 0.58 ppm 0.58ppm Mineral Oil 136 ppm 65 ppm Photochromic Dye Mixture 470 ppm 507 ppm

TABLE 3 Ingredient Formula 7 Formula 8 Formula 9 Formula 10 Formula 11Formula 12 Irgacure 819 531.2 ppm 462 ppm 565.9 ppm 226 ppm 443 ppm 294ppm Irgacure 184 18.7 ppm 144 ppm CN 384 0.77% 0.887% 0.78% 0.40% 0.61%CN 386 0.77% 0.887% 0.78% 0.53% 0.61% SR-348 72.4% 70.36% 58.20%  41.5%88.70%  SR-368 24.1% 23.87% 21.4%  7.0% SR-480 CD-540 18.7% 0.74% 97.76%SR-399 46.8% SR-239 1.86%  3.65% 20.1%  2.00% SR-506 10.0% CR-73 20.1%2.9% PRO-629 0.05% Tinuvin 770 UV Absorber Thermoplast Blue 0.567 ppm3.62 ppm 0.70 ppm 0.255 ppm 0.6 ppm 4.3 ppm Thermoplast Red 0.0147 ppm0.576 ppm 0.014 ppm 0.006 ppm 0.028 ppm 0.24 ppm Photochromic DyeMixture 450 ppm

TABLE 4 Ingredient Formula 13 Formula 14 Formula 15 Formula 16 Formula17 Formula 18 Irgacure 819 760 ppm 620 ppm 289 ppm 105 ppm 343 ppmIrgacure 184 CN 384 0.73% 0.34% 0.475% CN 386 0.73% 0.34%  1.00% 0.70%0.475% 2-ITX 188 ppm 141 ppm SR-348 89.00% 92.00%  98.90% SR-368 SR-480CD-540 97.57% 96.20%  99.28%  0.34% SR-399 SR-239  2.30% 2.30% 0.01%SR-506 SR-444 SR-454 10.00%  6.9% CR-73 PRO-629 Tinuvin 770 UV Absorber785 ppm Thermoplast Blue 4.9 ppm 5.1 ppm 0.508 ppm 0.35 ppm 0.69 ppmThermoplast Red 0.276 ppm 0.285 ppm 0.022 ppm 0.002 ppm 0.034 ppmDioctylphthalate 125 ppm Butyl stearate Photochromic Dye Mixture 499 ppm

TABLE 5 Ingredient Formula 19 Formula 20 Formula 21 Formula 22 Formula23 Formula 24 Irgacure 819 490 ppm 635 ppm 610 ppm 735 ppm 320 ppm 600ppm Irgacure 184 CN 384 0.680% 0.746% 0.705% 0.60% CN 386 0.680% 0.746%0.705% 0.60% 2-ITX SR-348 69.30% 68.60% SR-368 74.0% 22.10% SR-480CD-540 98.45% 92.60% 98.50%   1.0%  1.97% SR-399 SR-239  0.01%  3.86%0.16% SR-506 0.10% SR-444 29.30% SR-454 25.0%  7.40% CR-73 PRO-6290.007%  2.06% Tinuvin 770 UV Absorber Thermoplast Blue 0.37 ppm 0.507ppm 3.07 ppm 4.3 ppm 0.15 ppm 0.29 ppm Thermoplast Red 0.013 ppm 0.0126ppm 0.336 ppm 0.41 ppm 0.006 ppm 0.012 ppm Dioctylphthalate Butylstearate Photochromic Dye Mixture 442 ppm 497 ppm

TABLE 6 Ingredient Formula 25 Formula 26 Formula 27 Formula 28 Formula29 Formula 30 Formula 31 Irgacure 819 650 ppm 464 ppm 557 ppm 448 ppm460 ppm Irgacure 184 300 ppm CN 384 0.650%  0.70% CN 386 0.650%  0.70%2-ITX 600 ppm 120 ppm SR-348 39.10% SR-368 13.00% 19.60% 20.70% SR-48010.70% CD-540 88.96% 41.90%  1.60%  1.30% 99.94% 99.96% SR-399 SR-239SR-506 98.30% 79.00% 67.24% SR-444  9.70%  4.60% SR-454 CR-73 PRO-629Tinuvin 770 UV Absorber Thermoplast Blue 0.566 ppm 0.52 ppm 0.24 ppm0.19 ppm 0.467 ppm Thermoplast Red 0.02 ppm 0.013 ppm 0.01 ppm 0.008 ppm0.024 ppm Dioctylphthalate Butyl stearate 75 ppm 35 ppm Photochromic DyeMixture

In one embodiment, plastic lenses may be formed by disposing a mid-indexlens forming composition into the mold cavity of a mold assembly andirradiating the mold assembly with activating light. Coating materialsmay be applied to the mold members prior to filling the mold cavity withthe lens forming composition.

After filing the mold cavity of the mold assembly the mold assembly ispreferably placed in the lens curing unit and subjected to activatinglight. Preferably, actinic light is used to irradiate the mold assembly.A clear polycarbonate plate may be placed between the mold assembly andthe activating light source. The polycarbonate plate preferably isolatesthe mold assembly from the lamp chamber, thus preventing airflow fromthe lamp cooling fans from interacting with the mold assemblies. Theactivating light source may be configured to deliver from about 0.1 toabout 10 milliwatts/cm2 to at least one non-casting face, preferablyboth non-casting faces, of the mold assembly. Depending on thecomponents of the lens forming composition used the intensity ofactivating light used may be <1 milliwatt/cm². The intensity of incidentlight at the plane of the lens curing unit drawer is measured using anInternational Light IL-1400 radiometer equipped with an XRL140A detectorhead. This particular radiometer preferably has a peak detectionwavelength at about 400 nm, with a detection range from about 310 nm toabout 495 nm. The International Light IL-1400 radiometer and the XRL140Adetector head are both commercially available International Light,Incorporated of Newburyport, Mass.

After the mold assembly is placed within the lens curing unit, the moldassemblies are preferably irradiated with activating light continuouslyfor 30 seconds to thirty minutes, more preferably from one minute tofive minutes. Preferably, the mold assemblies irradiated in the absenceof a cooling air stream. After irradiation, the mold assemblies wereremoved from the lens curing unit and the formed lens demolded. Thelenses may be subjected to a post-cure treatment in the post-cure unit.

In general, it was found that the use of a photoinitiator (e.g., IRG-819and IRG-184) in the lens forming composition produces lenses with bettercharacteristics than lens formed using a co-initiator only. For example,formula 15, described in the Table 4, includes a monomer composition (amixture of SR-348 and SR-454) and a co-initiator (CN-386). When thislens forming composition was exposed to activating light for 15 min.there was no significant reaction or gel formation. It is believed thatthe co-initiator requires an initiating species in order to catalyzecuring of the monomer composition. Typically this initiating species isproduced from the reaction of the photoinitiator with activating light.

A variety of photoinitiators and photoinitiators combined withco-initiators may be used to initiate polymerization of the monomercomposition. One initiator system which may be used includesphotoinitiators IRG-819 and 2-ITX and a co-initiator, see Formulas17-18. Such a system is highly efficient at initiating polymerizationreactions. The efficiency of a polymerization catalyst is a measurementof the amount of photoinitiator required to initiate a polymerizationreaction. A relatively small amount of an efficient photoinitiator maybe required to catalyze a polymerization reaction, whereas a greateramount of a less efficient photoinitiator may be required to catalyzethe polymerization reaction. The IRG-819/2-ITX/co-initiator system maybe used to cure lenses forming compositions which include a UV absorbingcompound. This initiator system may also be used to form colored lenses.

An initiator system that is less efficient than theIRG-819/2-ITX/co-initiator system includes a mixture of thephotoinitiators IRG-819 and 2-ITX, see Formula 31. This system is lessefficient at initiating polymerization of lens forming compositions thanthe IRG-819/2-ITX/co-initiator system. The IRG-819/2-ITX system may beused to cure very reactive monomer compositions. An initiator systemhaving a similar efficiency to the IRG-819/2-ITX system includes amixture of IRG-819 and co-initiator, see Formulas 1-6, 8-9, 11, 14-15,19-22, and 25-26. The IRG-819/co-initiator system may be used to cureclear lenses which do not include a UV blocking compound andphotochromic lens forming compositions.

Another initiator system which may be used includes the photoinitiator2-ITX and a co-initiator. This initiator system is much less efficientat initiating polymerization reactions than the IRG-819/co-initiatorsystem. The 2-ITX/co-initiator system is preferably used for curingmonomer compositions which include highly reactive monomers.

The use of the above described mid-index lens forming compositions mayminimize or eliminate a number of problems associated with activatinglight curing of lenses. One problem typical of curing eyeglass lenseswith activating light is pre-release. Pre-release may be caused by anumber of factors. If the adhesion between the mold faces and theshrinking lens forming composition is not sufficient, pre-release mayoccur. The propensity of a lens forming composition to adhere to themold face, in combination with its shrinkage, determine how the processvariables are controlled to avoid pre-release. Adhesion is affected bysuch factors as geometry of the mold face (e.g., high-add flat-topbifocals tend to release because of the sharp change in cavity height atthe segment line), the temperature of the mold assembly, and thecharacteristics of the in-mold coating material. The process variableswhich are typically varied to control pre-release include theapplication of cooling fluid to remove exothermic heat, controlling therate of heat generation by manipulating the intensities and timing ofthe activating radiation, providing differential light distributionacross the thin or thick sections of the mold cavity manipulating thethickness of the molds, and providing in-mold coatings which enhanceadhesion. An advantage of the above described mid-index lens formingcompositions is that the composition appears to have enhanced adhesioncharacteristics. This may allow acceptable lenses to be produced over agreater variety of curing conditions. Another advantage is that higherdiopter lenses may be produced at relatively low pre-release rates,broadening the achievable prescription range.

Another advantage of the above described mid-index lens formingcompositions is that they tend to minimize problems associated withdripping during low intensity curing of lenses (e.g., in the 1 to 6milliwatt range). Typically, during the irradiation of the lens formingcomposition with activating light, small amounts of monomer may besqueezed out of the cavity and run onto the non-casting faces of themolds. Alternatively, during filling of the mold assembly with the lensforming composition, a portion of the lens forming composition may driponto the non-casting faces of the mold assembly. This “dripping” ontothe non-casting faces of the mold assembly tends to cause the activatinglight to focus more strongly in the regions of the cavity locatedunderneath the drippings. This focusing of the activating light mayaffect the rate of curing. If the rate of curing underneath thedrippings varies significantly from the rate of curing throughout therest of the lens forming composition, optical distortions may be createdin the regions below the drippings.

It is believed that differences in the rate of gelation between thecenter and the edge regions of the lens forming composition may causedripping to occur. During the curing of a lens forming composition, thematerial within the mold cavity tends to swell slightly during the gelphase of the curing process. If there is enough residual monomer aroundthe gasket lip, this liquid will tend to be forced out of the cavity andonto the non-casting faces of the mold. This problem tends to beminimized when the lens forming composition undergoes fast, uniformgelation. Typically, a fast uniform gelation of the lens formingcomposition may be achieved by manipulating the timing, intensities, anddistribution of the activating radiation. The above described mid-indexlens forming compositions, however, tend to gel quickly and uniformlyunder a variety of curing conditions, thus minimizing the problemscaused by dripping.

Another advantage of the above described mid-index lens formingcompositions is that the compositions tend to undergo uniform curingunder a variety of curing conditions. This uniform curing tends tominimize optical aberrations within the formed lens. This is especiallyevident during the formation of high plus power flattop lenses whichtend to exhibit optical distortions after the lens forming compositionis cured. It is believed that the activating radiation may be reflectedoff of the segment line and create local differences in the rate ofgelation in the regions of the lens forming composition that thereflected light reaches. The above described mid-index lens formingcompositions tend to show less optical distortions caused by variationsof the intensity of activating radiation throughout the composition.

Other advantages include drier edges and increased rigidity of theformed lens. An advantage of drier edges is that the contamination ofthe optical faces of the lens by uncured or partially cured lens formingcomposition is minimized.

In an embodiment, a lens forming composition may be cured into a varietyof different lenses. The lens forming composition includes an aromaticcontaining polyether polyethylenic functional monomer, a co-initiatorcomposition configured to activate curing of the monomer, and aphotoinitiator configured to activate the co-initiator composition inresponse to being exposed to activating light. The lens formingcomposition may include other components such as ultraviolet lightabsorbers and photochromic compounds. Lenses which may be cured usingthe lens forming composition include, but are not limited to, sphericsingle vision, aspheric single vision lenses, flattop bifocal lenses,and asymmetrical progressive lenses.

One lens forming composition, includes a mixture of the followingmonomers.

98.25% Ethoxylated₍₄₎bisphenol A dimethacrylate (CD-540) 0.75%Difunctional reactive amine coinitiator (CN-384) 0.75% Monofunctionalreactive amine coinitiator (CN-386) 0.15% Phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide (Irgacure-819) 0.10%2-(2H-Benzotriazol-2-yl)-4-(1,1,3,3-tetramethylbutyl)- phenol 0.87 ppmThermoplast Blue 684 0.05 ppm Thermoplast Red LB 454

Another lens forming composition includes a mixture of the followingmonomers. The presence of photochromic compounds in this compositionallows the composition to be used to form photochromic lenses.

97.09% Ethoxylated₍₄₎bisphenol A dimethacrylate (CD-540) 1.4%Difunctional reactive amine coinitiator (CN-384) 1.4% Monofunctionalreactive amine coinitiator (CN-386) 0.09% Phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide (Irgacure-8 19) 0.9 ppmThermoplast Red LB 454 50 ppm Variacrol Blue D 73.5 ppm Variacrol Yellow145 ppm Berry Red 29 ppm Palatinate Purple 55.5 ppm Corn Yellow 62 ppmSea Green 85 ppm Plum Red

A lens forming composition which includes an aromatic containingpolyether polyethylenic functional monomer, a co-initiator compositionand a photoinitiator may be used to form a variety of prescriptioneyeglass lenses, including eyeglass lenses which have a sphere powerranging from about +4.0 diopter to about −6.0 diopter. The lenses formedfrom this lens forming composition are substantially free ofdistortions, cracks, patterns and striations, and that have negligibleyellowing, in less than thirty minutes by exposing the lens formingcomposition to activating light and heat. An advantage of the lensforming composition is that it exhibits increased adhesion to the molds.This may reduce the incidence of premature release of the formed lensfrom the molds. Additionally, the use of adhesion promoting agents,typically applied to the molds to prevent premature release, may nolonger be necessary.

The increased adhesion of the lens forming composition to the moldsallows curing of the lens forming composition at higher temperatures.Typically, control of the temperature of the lens forming compositionmay be necessary to prevent premature release of the lens from themolds. Premature release may occur when the lens forming compositionshrinks as it is cured. Shrinkage typically occurs when the lens formingcomposition is rapidly heated during curing. Lens forming compositionswhich include an aromatic containing polyether polyethylenic functionalmonomer, a co-initiator composition and a photoinitiator may reduce theincidence of premature release. The increased adhesion of this lensforming composition may allow higher curing temperatures to be usedwithout increasing the incidence of premature release. It is alsobelieved that this lens forming composition may exhibit less shrinkageduring curing which may further reduce the chance of premature release.

An advantage of curing at higher temperatures is that an eyeglass lenshaving a high crosslink density may be formed. The crosslink density ofan eyeglass lens is typically related to the curing temperature. Curinga lens forming composition at a relatively low temperature leads to alower crosslink density than the crosslink density of a lens cured at ahigher temperature. Lenses which have a higher crosslink densitygenerally absorb tinting dyes substantially evenly without blotching orstreaking. Lenses which have a high crosslink density also may exhibitreduced flexibility.

METHODS OF FORMING PLASTIC LENSES

Plastic lenses may be formed by disposing a lens forming compositioninto the mold cavity of a mold assembly and irradiating the moldassembly with activating light. Coating materials may be applied to themold members prior to filling the mold cavity with the lens formingcomposition. The lens may be treated in a post-cure unit after thelens-curing process is completed.

The operation of the above described system to provide plastic lensesinvolves a number of operations. These operations are preferablycoordinated by the controller 50, which has been described above. Afterpowering the system, an operator is preferably signaled by thecontroller to enter the prescription of the lens, the type of lens, andthe type of coating materials for the lens. Based on these inputtedvalues the controller will preferably indicate to the operator whichmolds and gaskets will be required to form the particular lens.

The formation of lenses involves: 1) Preparing the mold assembly; 2)Filling the mold assembly with the lens forming composition; 3) Curingthe lens; 4) Post-curing the lens; and 5) Annealing the lens.Optionally, the lens may be coated before use. The formation of lensesmay be accomplished using the plastic lens curing apparatus describedabove.

The preparation of a mold assembly includes selecting the appropriatefront and back molds for a desired prescription and lens type, cleaningthe molds, and assembling the molds to form the mold assembly. Theprescription of the lens determines which front mold, back mold, andgasket are used to prepare the mold assembly. In one embodiment, a chartwhich includes all of the possible lens prescriptions may be used toallow a user to determine the appropriate molds and gaskets. Such achart may include thousands of entries, making the determination of theappropriate molds and gaskets somewhat time consuming.

In an embodiment, the controller 50 of the plastic lens curing apparatus10 (see FIG. 1) will display the appropriate front mold, back mold, andgasket identification markings when a prescription is submitted to thecontroller. The controller will prompt the user to enter the 1) themonomer type; 2) the lens type; 3) spherical power; 4) cylindricalpower; 5) axis; 6) add power, and 7) the lens location (i.e., right orleft lens). Once this information is entered the computer will determinethe correct front mold, back mold and gasket to be used. The controllermay also allow a user to save and recall prescription data.

FIG. 17 shows an embodiment of a front panel for the controller 50. Thecontroller includes an output device 610 and at least one input device.A variety of input devices may be used. Some input devices includepressure sensitive devices (e.g., buttons), movable data entry devices(e.g., rotatable knobs, a mouse, a trackball, or moving switches), voicedata entry devices (e.g., a microphone), light pens, or a computercoupled to the controller. Preferably the input devices include buttons630, 640, 650 and 660 and a selection knob 620. The display panelpreferably displays the controller data requests and responses. Theoutput device may be a cathode ray tube, an LCD panel, or a plasmadisplay screen.

When initially powered, the controller will preferably display a mainmenu, such as the menu depicted in FIG. 17. If the main menu is notdisplayed, a user may access the main menu by pressing button 650, whichmay be labeled Main Menu. In response to activating the Main Menu button650, the controller will cause the main menu screen to be displayed. Asdepicted in FIG. 17, a display screen offers a number of initial optionson the opening menu. The options may include 1) NEW Rx; 2) EDIT Rx; and3) VIEW Rx. The main menu may also offer other options which allow theoperator to access machine status information and instrument setupmenus. The scrolling buttons 630 preferably allow the user to navigatethrough the options by moving a cursor 612 which appears on the displayscreen to the appropriate selection. Selection knob 620 is preferablyconfigured to be rotatable to allow selection of options on the displayscreen. Knob 620 is also configured to allow entry of these items. Inone embodiment, selection knob 620 may be depressed to allow data entry.That is, when the appropriate selection is made, the knob may be pusheddown to enter the selected data. In the main menu, when the cursor 612is moved to the appropriate selection, the selection may be made bydepressing the selection knob 620.

Selection of the NEW Rx menu item will cause the display screen tochange to a prescription input menu, depicted in FIG. 18. Theprescription input menu will preferably allow the user to enter datapertaining to a new lens type. The default starting position will be thelens monomer selection box. Once the area is highlighted, the selectionknob 620 is rotated to make a choice among the predetermined selections.When the proper selection is displayed, the selection knob may be pusheddown to enter the selection. Entry of the selection may also cause thecursor to move to the next item on the list. Alternatively, a user mayselect the next item to be entered using the scrolling arrows 630.

Each of the menu items allows entry of a portion of the lensprescription. The lens prescription information includes 1) the monomertype; 2) the lens type; 3) lens location (i.e., left lens or rightlens); 4) spherical power; 5) cylindrical power; 6) axis; and 7) addpower. The monomer selection may include choices for either clear orphotochromic lenses. The lens type item may allow selection betweenspheric single vision, aspheric single vision lenses, flattop bifocallenses, and asymmetrical progressive lenses. The sphere item allows thesphere power of the lens to be entered. The cylinder item allows thecylinder power to be entered. The axis item allows the cylinder axis tobe entered. The add item allows the add power for multifocalprescriptions to be added. Since the sphere power, cylinder power,cylinder axis, and add power may differ for each eye, and since themolds and gaskets may be specific for the location of the lens (i.e.,right lens or left lens), the controller preferably allows separateentries for right and left lenses. If an error is made in any of theentry fields, the scrolling arrows 630 preferably allow the user to movethe cursor to the incorrect entry for correction.

After the data relating to the prescription has been added, thecontroller may prompt the user to enter a job number to save theprescription type. This preferably allows the user to recall aprescription type without having to renter the data. The job number mayalso be used by the controller to control the curing conditions for thelens. The curing conditions typically vary depending on the type andprescription of the lens. By allowing the controller access to theprescription and type of lens being formed, the controller mayautomatically set up the curing conditions without further input fromthe user.

After the job is saved, the display screen will preferably displayinformation which allows the user to select the appropriate front mold,back mold and gasket for preparing the lens, as depicted in FIG. 19.This information is preferably generated by the use of a stored databasewhich correlates the inputted data to the appropriate lenses and gasket.The prescription information is also summarized to allow the user tocheck that the prescription has been entered correctly. The mold andgasket information may be printed out for the user. A printer may beincorporated into the controller to allow print out of this data.Alternatively, a communication port may be incorporated into thecontroller to allow the data to be transferred to a printer or personalcomputer. Each of the molds and gaskets has a predeterminedidentification marking. Preferably, the identification markings arealphanumeric sequences. The identification markings for the molds andgasket preferably correspond to alphanumeric sequences for a library ofmold members. The user, having obtained the mold and gasketidentification markings, may then go to the library and select theappropriate molds and gaskets.

The controller is preferably configured to run a computer softwareprogram which, upon input of the eyeglass prescription, will supply theidentification markings of the appropriate front mold, back mold andgasket. The computer program includes a plurality of instructionsconfigured to allow the controller to collect the prescriptioninformation, determine the appropriate front mold, back mold, and gasketrequired to a form a lens having the inputted prescription, and displaythe appropriate identification markings for the front mold, back moldand gasket. In one embodiment, the computer program may include aninformation database. The information database may include amultidimensional array of records. Each records may include data fieldscorresponding to identification markings for the front mold, the backmold, and the gasket. When the prescription data is entered, thecomputer program is configured to look up the record corresponding tothe entered prescription. The information from this record may betransmitted to the user, allowing the user to select the appropriatemolds and gasket.

In one embodiment the information database may be a three dimensionalarray of records. An example of a portion of a three dimensional arrayof records is depicted in Table 9. The three dimensional array includesarray variables of sphere, cylinder, and add. A record of the threedimensional array includes a list of identification markings. Preferablythis list includes identification markings for a front mold (for eithera left or right lens), a back mold and a gasket. When a prescription isentered the program includes instructions which take the cylinder,sphere and add information and look up the record which is associatedwith that information. The program obtains from the record the desiredinformation and transmits the information to the user. For example, if aprescription for left lens having a sphere power of +1.00, a cylinderpower of −0.75 and an add power of 2.75 is entered, the front moldidentification marking will be FT-34, the back mold identificationmarking will be TB-101, and the gasket identification marking will beG25. These values will be transmitted to the user via an output device.The output device may include a display screen or a printer. It shouldbe understood that the examples shown in Table 9 represent a smallportion of the entire database. The sphere power may range from +4.00 to−4.00 in 0.25 diopter increments, the cylinder power may range from 0.00diopters to −2.00 diopters in 0.25 diopter increments, and the add powermay range from +1.00 to +3.00 in 0.25 diopter increments.

TABLE 9 IDENTIFICATION MARKINGS ARRAY VARIABLES Front Front SphereCylinder Add (Right) (Left) Back Gasket +1.00 −0.75 +1.25 FT-21 FT-22TB-101 G25 +1.00 −0.75 +1.50 FT-23 FT-24 TB-101 G25 +1.00 −0.75 +1.75FT-25 FT-26 TB-101 G25 +1.00 −0.75 +2.00 FT-27 FT-28 TB-101 G25 +1.00−0.75 +2.25 FT-29 FT-30 TB-101 G25 +1.00 −0.75 +2.50 FT-31 FT-32 TB-101G25 +1.00 −0.75 +2.75 FT-33 FT-34 TB-101 G25 +1.00 −0.75 +3.00 FT-35FT-36 TB-101 G25 +0.75 −0.75 +1.00 FT-19 FT-20 TB-102 G25 +0.75 −0.75+1.25 FT-21 FT-22 TB-102 G25 +0.75 −0.75 +1.50 FT-23 FT-24 TB-102 G25+0.75 −0.75 +1.75 FT-25 FT-26 TB-102 G25 +0.75 −0.75 +2.00 FT-27 FT-28TB-102 G25 +0.75 −0.75 +2.25 FT-29 FT-30 TB-102 G25 +0.75 −0.75 +2.50FT-31 FT-32 TB-102 G25 +0.75 −0.75 +2.75 FT-33 FT-34 TB-102 G25 +0.75−0.75 +3.00 FT-35 FT-36 TB-102 G25 +0.50 −0.75 +1.00 FT-19 FT-20 TB-103G25 +0.50 −0.75 +1.25 FT-21 FT-22 TB-103 G25

A second information database may include information related to curingthe lens forming composition based on the prescription variables. Eachrecord may include information related to curing clear lenses (i.e.,non-photochromic lenses) and photochromic lenses. The curing informationmay include filter information, initial curing dose information,postcure time and conditions, and anneal time. An example of a portionof this database is depicted in Table 10. Curing conditions typicallydepend on the sphere power of a lens, the type of lens being formed(photochromic or non-photochromic), and whether the lens will be tintedor not. Curing information includes type of filter being used, initialdose conditions, postcure time, and anneal time. A filter with a 50 mmaperture (denoted as “50 mm”) or a clear plate filter (denoted as“clear”) may be used. Initial dose is typically in seconds, with theirradiation pattern (e.g., top and bottom, bottom only) being alsodesignated. The postcure time represents the amount of time the moldassembly is treated with activating light and heat in the postcure unit.The anneal time represents the amount of time the demolded lens istreated with heat after the lens is removed from the mold assembly.While this second database is depicted as a separate database, thedatabase may be incorporated into the mold and gasket database by addingthe lens curing information to each of the appropriate records.

The controller may also be configured to warn the user if the lens poweris beyond the range of the system or if their mold package does notcontain the necessary molds to make the desired lens. in these cases,the user may be asked to check the prescription information to ensurethat the proper prescription was entered.

The controller may also be used to control the operation of the variouscomponents of the plastic lens curing apparatus. A series of inputdevices 640 may allow the operation of the various components of thesystem. The input devices may be configured to cause the commencement ofthe lens coating process (640 a), the cure process (640 b), the postcureprocess (640 c), and the anneal process (640 d).

In an embodiment, activating any of the input devices 640 may cause ascreen to appear requesting a job number corresponding to the type oflenses being formed. The last job used may appear as a default entry.The user may change the displayed job number by cycling through thesaved jobs. When the properjob is displayed the user may enter the jobby depressing the selection knob.

TABLE 10 CURING INFORMATION LENS INFORMATION Initial Postcure AnnealSphere Lens Type Tinted Filter Dose Time Time +2.25 Clear No 50 mm 90Sec. 13 Min. 7 Min. Top and Bottom +2.25 Clear Yes 50 mm 90 Sec. 15 Min.7 Min Top and Bottom +2.25 Photochromic No 50 mm 90 Sec. 13 Min. 7 Min.Top and Bottom +2.00 Clear No Clear 7 Sec. Bottom 13 Min. 7 Min. +2.00Clear Yes Clear 7 Sec. Bottom 15 Min. 7 Min. +2.00 Photochromic No Clear15 Sec. Bottom 13 Min. 7 Min.

After the job has been entered, the system will be ready to commence theselected function. Activating the same input device again (e.g.,depressing the button) will cause the system to commence the selectedfunction. For example, pressing the cure button a second time may causea preprogrammed cure cycle to begin. After the selected function iscomplete the display screen may display a prompt informing the user thatthe action is finished.

The controller may be configured to prevent the user from using curingcycles other than those that have been prescribed by the programmer ofthe controller. After a prescription is entered, the job enters the workstream where the controller allows only the prescribed curingconditions. Timers (set by the algorithm picked at prescription input)may run constantly during the lens cycle to monitor doses and deliverboth audible and visible prompts to the user of at times of transitionin the process. The system tracks job completion and status and givesvisual representation of job status in the view job screen. Boxes at thebottom of the screen are checked as the necessary steps are competed. Insensitive parts of the lens cycle, no deviation from the establishedmethod is allowed. Operator discretion is allowed when the process isnot time critical. The software warns the user during procedures thatwill interrupt jobs during their execution, erase jobs that are notfinished, rerun jobs that are not finished, etc.

The system may be configured to prevent a new cure cycle from beingstarted until the previous job's cure is finished. This “gatekeeper”function ensures post cure chamber availability during time sensitivetransitions. When the cure stage is finished, both audible and visualprompts instruct the user to place the cavities in the post cure area.

The main menu may also include selections allowing a saved job to beedited. Returning to the main menu screen, depicted in FIG. 17,selecting the edit menu item will cause an interactive screen to bedisplayed similar to the input screen. This will allow a user to changethe prescription of a preexisting job. The view menu item will allow auser to view the prescription information and mold/gasket selectioninformation from an existing job.

Once the desired mold and gasket information has been obtained, theproper molds and gasket are selected from a collection of molds andgaskets. The molds may be placed into the gasket to create a moldassembly. Prior to placing the molds in the gasket, the molds arepreferably cleaned. The inner surface (i.e., casting surface) of themold members may be cleaned on a spin coating unit 20 by spraying themold members with a cleaning solution while spinning the mold members.Examples of cleaning solutions include methanol, ethanol, isopropylalcohol, acetone, methyl ethyl ketone, or a water based detergentcleaner. Preferably, a cleaning solution which includes isopropylalcohol is used to clean the mold members. As the mold member iscontacted with the cleaning solution, dust and dirt may be removed andtransferred into the underlying dish 115 of the curing unit. After asufficient amount of cleaning solution has been applied the mold membersmay be dried by continued spinning without the application of cleaningsolution.

In an embodiment, the inner surface, i.e., the casting face, of thefront mold member may be coated with one or more hardcoat layers beforethe lens forming composition is placed within the mold cavity.Preferably, two hardcoat layers are used so that any imperfections, suchas pin holes in the first hardcoat layer, are covered by the secondhardcoat layer. The resulting double hardcoat layer is preferablyscratch resistant and protects the subsequently formed eyeglass lens towhich the double hardcoat layer adheres. The hardcoat layers arepreferably applied using a spin coating unit 20. The mold member ispreferably placed in the spin coating unit and the coating materialapplied to the mold while spinning at high speeds (e.g., between about900 to 1000 RPM). After a sufficient amount of coating material has beenapplied, the coating material may be cured by the activating lightsource disposed in the cover. The cover is preferably closed andactivating light is preferably applied to the mold member while the moldmember is spinning at relatively low speeds (e.g., between about 150 to250 RPM). Preferably control of the spinning and the application ofactivating light is performed by controller 50. Controller 50 ispreferably configured to prompt the operator to place the mold memberson the coating unit, apply the coating material to the mold member, andclose the cover to initiate curing of the coating material.

In an embodiment, the eyeglass lens that is formed may be coated with ahydrophobic layer, e.g. a hardcoat layer. The hydrophobic layerpreferably extends the life of the photochromic pigments near thesurfaces of the lens by preventing water and oxygen molecules fromdegrading the photochromic pigments.

In a preferred embodiment, both mold members may be coated with a curedadhesion-promoting composition prior to placing the lens formingcomposition into the mold cavity. Providing the mold members with suchan adhesion-promoting composition is preferred to increase the adhesionbetween the casting surface of the mold and the lens formingcomposition. The adhesion-promoting composition thus reduces thepossibility of premature release of the lens from the mold. Further, itis believed that such a coating also provides an oxygen and moisturebarrier on the lens which serves to protect the photochromic pigmentsnear the surface of the lens from oxygen and moisture degradation. Yetfurther, the coating provides abrasion resistance, chemical resistance,and improved cosmetics to the finished lens.

In an embodiment, the casting face of the back mold member may be coatedwith a material that is capable of being tinted with dye prior tofilling the mold cavity with the lens forming composition. This tintablecoat preferably adheres to the lens forming composition so that dyes maylater be added to the resulting eyeglass lens for tinting the lens. Thetintable coat may be applied using the spin coating unit as describedabove.

The clean molds are placed on the gasket to form a mold assembly. Thefront mold is preferably placed on the gasket first. For single visionprescriptions, the front mold does not have to be placed in anyparticular alignment. For flat-top bifocal or progressive front molds,the molds are preferably aligned with alignment marks positioned on thegasket. Once the front mold has been placed into the gasket, the backmold is placed onto the gasket. If the prescription calls for cylinderpower, the back mold must be aligned with respect to the front mold. Ifthe prescription is spherical (e.g., the lens has no cylinder power),the back mold may be placed into the gasket without any specialalignment. Once assembled the mold assembly will be ready for filling.

The controller may prompt the user to obtain the appropriate lensforming composition. In one embodiment, the controller will inform theuser of which chemicals and the amounts of each chemical that isrequired to prepare the lens forming composition. Alternatively, thelens forming compositions may be preformed. In this case the controllermay indicate to the operator which of the preformed lens formingcompositions should be used.

In an embodiment, dyes may be added to the lens forming composition. Itis believed that certain dyes may be used to attack and encapsulateambient oxygen so that the oxygen may be inhibited from reacting withfree radicals formed during the curing process. Also, dyes may be addedto the composition to alter the color of an unactivated photochromiclens. For instance, a yellow color that sometimes results after a lensis formed may be “hidden” if a blue-red or blue-pink dye is present inthe lens forming composition. The unactivated color of a photochromiclens may also be adjusted by the addition of non-photochromic pigmentsto the lens forming composition.

In a preferred technique for filling the lens molding cavity 382, theannular gasket 380 is placed on a concave or front mold member 392 and aconvex or back mold member 390 is moved into place. The annular gasket380 is preferably pulled away from the edge of the back mold member 390at the uppermost point and a lens forming composition is preferablyinjected into the lens molding cavity 382 until a small amount of thelens forming composition is forced out around the edge. The excess isthen removed, preferably, by vacuum. Excess liquid that is not removedcould spill over the face of the back mold member 390 and cause opticaldistortion in the finished lens.

The lens forming composition is typically stored at temperatures belowabout 100° F. At these temperatures, however, the lens formingcomposition may be relatively viscous. The viscosity of the solution maymake it difficult to fill a mold cavity without creating bubbles withinthe lens forming composition. The presence of bubbles in the lensforming composition may cause defects in the cured eyeglass lens. Toreduce the viscosity of the solution, and therefore reduce the incidenceof air bubbles during filling of the mold cavity, the lens formingcomposition may be heated prior to filling the mold cavity. In anembodiment, the lens forming composition may be heated to a temperatureof about 70° F. to about 220° F., preferably from about 130° F. to about170° F. prior to filing the mold cavity. Preferably, the lens formingcomposition is heated to a temperature of about 150° F. prior to fillingthe mold cavity.

The lens forming composition may be heated by using an electric heater,an infrared heating system, a hot air system, a hot water system, or amicrowave heating system. Preferably, the lens forming composition isheated in a monomer heating system, such as depicted in FIGS. 20 and 21.FIG. 20 depicts an isometric view of the monomer heating system and FIG.21 depicts a side view of the monomer heating system depicted in FIG.20. The monomer heating system includes a body 1500 configured to holdthe lens forming composition and a valve 1520 for transferring theheated lens forming composition from the body to a mold assembly. Themonomer heating system may also include a mold assembly support 1540 forholding a mold assembly 1550 proximate the valve. The monomer heatingsystem may also include an opening for receiving a container 1560 thatholds a monomer composition.

FIG. 22 depicts a cross sectional view of the monomer heating system.The body includes a monomer 1502 and top 1504. The top of the body 1504may include an opening 1506 sized to allow a fluid container 1560 to beinserted within the opening. The opening may be sized such that thebottle rests at an angle when placed in the opening, as depicted in FIG.22. In some embodiments, the angle of the bottle may be between about 5and about 45 degrees. In one embodiment, the opening is sized to receivea cap 1562 of a fluid container 1560. The cap 1562 and the opening 1506may be sized to allow the cap to be easily inserted through the opening.If all of the fluid in the fluid container 1562 will fit in the body1500 of the monomer heating system, the cap 1562 may be removed and thebottle placed in the opening. The fluid container 1560 may be left untilall of the fluid has been emptied into the body 1500. The fluidcontainer 1560 may be removed or left in the opening after the monomerhas emptied into the body 1500.

In another embodiment, the fluid container 1560 may include a selfsealing cap 1562 coupled to the fluid container body 1569. A crosssectional view of the fluid container 1560 with a self sealing cap isdepicted in FIG. 23. The self sealing cap 1562 may be configured to fitwithin the opening 1506 in the body. The self sealing cap 1562 may becouplable to the fluid container body 1569 via a threaded fit (e.g.,screwed onto the fluid container) or, alternatively, may be fastened tothe fluid container body using a suitable adhesive. In anotherembodiment, the cap 1562 may be fastened to the fluid container body byboth a threaded fit and the use of a suitable adhesive.

The cap 1562 includes, in one embodiment, a fluid control member 1564and an elastic member 1566. The fluid control member 1564 may have asize and shape to substantially fit against an inner surface of the topof cap 1562 such that the fluid control member inhibits the passage offluid out of the fluid container. The elastic member 1566 may be coupledto the fluid control member 1564 such that the elastic member exerts aforce on the fluid control member such that the fluid control member isforced against the top inner surface of the cap. In one embodiment, theelastic member may be a spring while the fluid control member may be asubstantially spherical object. In a normal resting position, theelastic member 1566 exerts a force against the fluid control member1564, forcing it against the top inner surface 1568 of the cap. The topof the cap is sized to inhibit the passage of the spherical object 1564through the top 1568 of the cap. Thus, when not is use, the fluidcontrol member 1564 is forced against the top 1568 of the cap 1562,forming a seal that inhibits the flow of a fluid through the cap.

When the monomer heating station is to be filled, the fluid container1560 may be inserted into opening 1506 of the body 1500. If a selfsealing cap is used, as depicted in FIG. 23, the body may be configuredto force the fluid control member away from the top of the fluidcontainer. As the fluid control member is moved away from the top of thecap, the fluid will flow around the fluid control member and out of thefluid container. In one embodiment, the body 1500 may include aprojection 1508 (see FIG. 23) that extends from the bottom 1502 of thebody and toward the opening. When the fluid container is inserted intothe opening, the projection may hit the fluid control member forcing thefluid control member away from the top. When the bottle is removed, theprojection will move away from the fluid control member and the fluidcontrol member may be pushed back to its resting position, thusinhibiting the further flow of fluid from the fluid container.

A heating system 1510 is preferably coupled to the body. The heatingsystem 1510 is preferably configured to heat the lens formingcomposition to a temperature of between about 80° F. to about 220° F.Preferably a resistive heater is used to heat the lens formingcomposition. Other heating systems such as hot air system, hot watersystems, and infrared heating systems may also be used. In oneembodiment, the heating system may include a silicon pad heater. Asilicon pad heater includes one or more of resistive heating elementsembedded within a silicon rubber material.

The heating system is preferably disposed within the body, as depictedin FIG. 22. In an embodiment, the body may be divided into a mainchamber 1512 and a heating system chamber 1514. The lens formingcomposition may be disposed within the main chamber 1514, while theheating system 1510 is preferably disposed within the heating systemchamber 1512. The heating system chamber 1512 preferably isolates theheating system 1510 from the main chamber 1512 such that the lensforming composition is inhibited from contacting the heating system.Typically, the heating system 1510 may attain temperatures significantlyhigher than desired. If the heating system 1510 were to come intocontact with the lens forming composition, the higher temperature of theheating system may cause the contacted lens forming composition tobecome partially polymerized. By isolating the heating system 1510 fromthe lens forming composition such partial polymerization may be avoided.To further prevent partial polymerization, the heating system ispreferably insulated from the bottom surface of the main chamber. Aninsulating material may be placed between the heating system and thebottom of the main chamber. Alternatively, an air gap may be formedbetween the heating system and the bottom of the main chamber to preventoverheating of the bottom of the main chamber.

A thermostat 1530 may be placed within the chamber, in contact witheither the lens forming composition and/or the heating system chamber.In another embodiment, the thermostat may be placed in the heatingsystem chamber between the main chamber and the heating element. Whenpositioned in this manner, the thermostat may be more response tochanges in the temperature of the monomer. The thermostat 1530preferably monitors the temperature of the lens forming composition. Inan embodiment, the thermostat may be a bi-metal immersion temperatureswitch. Such thermostats may be obtained from Nason, West Union, SouthCarolina. The temperature switch may be configured for a specifictemperature by the manufacturer. For example, the optimal monomercomposition may be about 150° F. The temperature switch may be preset bythe manufacturer for about 150° F. When the monomer solution is below150° F., the switch may be in an “on” state, which causes the heatingsystem to continue operating. Once the temperature of the monomersolution reaches about 150° F., the temperature switch may change to an“off” state. In the off state the heating system may be switched off. Asthe temperature of the monomer solution cools to below 150° F., theswitch may cause the heating system to turn back on.

Alternatively, a controller 1570 may be coupled to a thermocouple 1530and the heating system 1510. The thermocouple 1530 may provide a signalto the controller that indicates a temperature determined by thethermocouple. The thermocouple may be positioned within an aluminumblock disposed within the main chamber and adjacent to the heatingsystem chamber. The temperature detected by the thermocouple may be acombination of the temperature of the heating system chamber wall andthe lens forming composition. The controller 1540 may monitor thetemperature of the lens forming composition via the signals produced bythermocouple 1530 and controls the heating system 1510 to keep the lensforming composition at a predetermined temperature. For example, as thelens forming composition becomes cooler the controller may activate theheating system 1510 to heat the lens forming composition back to thedesired temperature. The controller 1540 may be a computer, programmablelogic controller, or any of other known controller systems known in theart. These systems may include a proportional-integral (“PI”) controlleror a proportional-integral-derivative (“PID”) controller.

A body 1500 may be in the form of a small volume conduit fortransferring the lens forming composition out of the body. The use of asmall volume conduit may minimize the amount of monomer solution that isin contact with the heating system at any given time. Monomer solutionpasses through the body and exits the body via the outlet valve 1520.

A fluid monitor 1580 may be used to monitor the level of fluid in thebody 1500. A fluid monitor 1580 may be positioned within the body 1500.Fluid monitors are commercially available from Gems Sensors Inc.,Plainville, CT. IN one embodiment model ELS-1100HT from Gems Sensors maybe used. The fluid monitor may be configured to monitor the level offluid in the body 1500. If the fluid level drops below a preselectedminimum, the fluid sensor may produce a signal to a controller. Acontroller may be coupled to the monomer heating system (e.g.,controller 1570) or may be part of the lens forming apparatus (e.g.,controller 50). In one embodiment, the controller may produce a warningmessage when a low fluid level signal is received from the fluid sensor.The warning message may be an alphanumeric readout on a controlleroutput device (e.g., and LCD screen) or the warning message may involvecausing a light to turn on signifying the low fluid level. Thecontroller may also be configured to turn the heating system 1510 offwhen the fluid level within the body is too low.

Outlet valve 1520 is positioned near the outlet of the body. The outletvalve includes an elongated member 1522 and a movable member 1524 foraltering the position of the elongated member, as depicted in FIG. 22.The elongated member 1522 preferably inhibits the flow of lens formingcomposition through the conduit when the elongated member is in a closedposition. The elongated member may be moved into an open position suchthat the lens forming composition may flow through the conduit.

As depicted in FIG. 22, the elongated member 1522 is in an openposition. The elongated member 1522 is preferably oriented perpendicularto the longitudinal axis of the body 1500, as depicted in FIG. 22. Theelongated member 1522 resides in a channel 1526 extending through thetop 1504 of the body 1500. When in the open position, the elongatedmember 1522 is positioned away from the outlet of the body. The end ofthe elongated member, as depicted in FIG. 22, has been moved past aportion of the bottom surface 1502 of the conduit such that the lensforming solution may flow through the conduit and out of the body. Theelongated member may be positioned to control the flow rate of the lensforming composition through the conduit. For example, as depicted inFIG. 22, the elongated member, although in an open position, stillpartially blocks the conduit, thus partially inhibiting flow of the lensforming composition through the conduit. As the elongated member ismoved further away from the outlet, the flow may of the lens formingcomposition may increase. The flow rate of the lens forming compositionmay reach a maximum when the elongated member no longer blocks theconduit.

In a closed position, the elongated member 1522 may extend to the bottomsurface 1502 near the outlet. Preferably, the elongated member 1522extends past the outer surface of the bottom of the body proximate theoutlet, when in the closed position. Configuring the elongated member1522 such that it extends past the outer surface of the conduit mayinhibit any residual lens forming composition from building up near theoutlet. As the elongated member 1522 is extended toward the outlet anylens forming composition present may be forced out, leaving the outletsubstantially clear of lens forming composition. The outlet may besubsequently cleaned by removing the excess lens forming compositionfrom the outer surface of the conduit and the elongated member.

The interaction of the elongated member 1522 with the movable member1524 allows the elongated member to be positioned in either a closed oropen position. The movable member 1524 preferably includes a pluralityof threads the interact with complimentary threads along the elongatemember 1526. Rotation of the movable member may cause the elongatedmember to move away from or toward the outlet, depending on thedirection of rotation of the movable member.

A mold assembly holder 1540 may be coupled to the body of the monomerheating system, as depicted in FIG. 22. The mold assembly holder 1540 isconfigured to hold the mold assembly at a preferred location withrespect to the outlet of the body 1500. he mold assembly holder maysecure the mold assembly during filling. In one embodiment, the moldsassembly holder is spring mounted to the bottom surface of the monomerheating system. The mold assembly holder includes an arm 1542 that iscoupled to the body 1500 by hinge 1544. The hinge allows the moldassembly holder to be rotated away form or toward the body 1500 of themonomer heating solution. Hinge 1544 may be spring loaded such that aconstant force is exerted on the arm, forcing the arm toward the bottomof the body 1500. To place the mold assembly 1550 on the mold assemblyarm 1544, the arm may be rotated away from the body and the moldassembly placed onto a portion of the arm configured to hold the moldassembly. The portion of the arm configured to hold the mold assemblymay include a clamping system to secure the mold assembly.

To fill the mold assembly, the mold assembly is placed on the moldassembly holders and positioned proximate to the outlet. The monomersolution is preferably introduced into the body of the fill station andheated to a temperature of about 150° F. After the mold assembly is inplace, the valve of the mold fill station is aligned with a fill port ofthe mold assembly. The lens forming composition is now flowed throughthe valve and into the mold assembly. The movable member 1524, may beadjusted to control the flow rate of the monomer.

After the mold assembly is filled, any monomer which may have spilled onthe surface of the molds is removed using a lint free wipe. Excessmonomer that may be around the edge of the filling port may be removedby using a micro vacuum unit. The mold assembly may be inspected toinsure that the mold cavity is filled with monomer. The mold assembly isalso inspected to insure that no air bubbles are present in the moldcavity. Any air bubbles in the mold cavity may be removed by rotatingthe mold assembly such that the air bubbles rise to the top of theassembly.

The heating of the monomer solution may be coordinated with the entry ofa prescription using a controller. In one embodiment, the monomerheating system may be electrically coupled to a lens forming apparatus,such as the apparatus depicted in FIG. 1. The monomer may have portsthat are appropriate for using standard data transfer cables to coupleto ports that are disposed on the lens forming apparatus. The operationof the monomer heating system may thus coordinated with the operation ofthe lens forming apparatus. In some embodiments, it may be desirable tominimize the amount of time a monomer solution is heated. In theseinstances may be desirable to heat the monomer solution just beforefilling the mold assembly. The controller 50 of the lens formingapparatus may be configured to coordinate the filling operation with theneeds of an operator.

When forming a prescription lens, an operator may first enter theprescription into the controller 50 as described above. Once theprescription has been entered, the operator typically spends some timefinding and cleaning the appropriate molds for the prescription andassembling the molds with a gasket. In one embodiment, the controllermay signal a monomer heating system to begin heating the monomersolution when a prescription is entered. By the time the mold assemblyhas been assembled, the monomer solution may be at or near the desiredtemperature. This may minimize the amount of time required by theoperator to prepare and fill the mold assembly. In some instances theoperator may, after preparing a first prescription enter additionalprescriptions to process. In this case, the monomer heating system maybe left in an “on” state. If a prescription is not entered after apredetermined amount of time, the controller may turn off the monomerheating system, so that the monomer in the system does not remain in aheated state for long periods of time. In some embodiments, thepredetermined amount of time may be about 10 or more minutes.

After filing the mold assembly, the lens forming composition may becured using a lens curing apparatus. In one embodiment, the curing ofthe lens forming composition may be accomplished by a procedureinvolving the application of heat and activating light to the lensforming composition. Initially, activating light is directed toward atleast one of the mold members. The activating light is directed for asufficient time to initiate curing of the lens forming composition.Preferably, the activating light is directed toward at least one of themold members for a time of less than about 2 minutes. In someembodiments, the activating light is directed toward at least one of themold members for a time of less than about 25 seconds. In otherembodiments, the activating light is directed toward at least one of themold members for a time of less than about 10 seconds. The activatinglight is preferably stopped before the lens forming composition iscompletely cured.

After the curing is initiated, the mold assembly may be transferred to apost cure unit. In the post cure unit the mold assembly is preferablytreated with additional activating light and heat to further cure thelens forming composition. The activating light may be applied from thetop, bottom, or from both the top and bottom of the curing chamberduring the post cure process. The lens forming composition may exhibit ayellow color after the curing is initiated. It is believed that theyellow color is produced by the photoinitiator. As the lens formingcomposition cures, the yellow color may gradually disappear as thephotoinitiator is used up. Preferably, the mold assembly is treated inthe post cure unit for a time sufficient to substantially remove theyellow color from the formed eyeglass lens. The mold assembly may betreated in the post cure unit for a time of up to about 15 minutes,preferably for a time of between about 10 minutes to 15 minutes. Afterthe lens is treated in the post cure unit, the formed eyeglass lens maybe demolded and placed back into the post cure unit.

TABLE 11 CURING INFORMATION LENS INFORMATION Postcure Anneal Sphere LensType Tinted Filter Initial Dose Time Time +4.00 to Clear No 50 mm 90Sec. 13 Min. 7 Min. +2.25 Back and Front +4.00 to Clear Yes 50 mm 90Sec. 15 Min. 7 Min. +2.25 Back and Front +4.00 to Photo 50 mm 90 Sec. 13Min. 7 Min. +2.25 Back and Front +2.00 to Clear No Clear Plate 7 Sec.Front 13 Min. 7 Min. −4.00 +2.00 to Clear Yes Clear Plate 7 Sec. Front15 Min. 7 Min. −4.00 +2.00 to Photo Clear Plate 15 Sec. Front 13 Min. 7Min. plano −0.25 to Photo Clear Plate 20 Sec. 13 Min. 7 Min. −4.00 Back,w/ 7 Sec. Front starting @ 13 Sec. elapsed time.

In some instances, it may be desirable to subject the lens to an annealprocess. When a lens, cured by the activating light, is removed from amold assembly, the lens may be under a stressed condition. It isbelieved that the power of the lens can be more rapidly brought to afinal resting power by subjecting the lens to an anneal treatment torelieve the internal stresses developed during the cure. Prior toannealing, the lens may have a power that differs from the desired finalresting power. The anneal treatment is believed to reduce stress in thelens, thus altering the power of the lens to the desired final restingpower. Preferably, the anneal treatment involves heating the lens at atemperature between about 200° F. to 225° F. for a period of up to about10 minutes. The heating may be performed in the presence or absence ofactivating light.

The post-cure and anneal times given in Table II are strictly exemplaryof the particular system described herein. It should be understood thatthe time for the post-cure and anneal process may vary if the intensityof the lamps or the temperature of the process is altered. For example,increasing the intensity of light used during the post-cure process mayallow a shorter post-cure time. Similarly, reducing the temperature ofthe post-cure unit during the annealing process may cause an increase inthe anneal time. Generally, the post-cure process is believed to berelated to the time required to substantially complete curing of thelens forming composition. The anneal process is believed to be relatedto the amount of time required to bring the formed lens to its finalresting power.

The use of a lens forming composition which includes an aromaticcontaining polyether polyethylenic functional monomer, a co-initiatorcomposition and a photoinitiator allows much simpler curing conditionsthan other lens forming compositions. While pulsed activated lightcuring sequences may be used to cure the lenses, continuous activatinglight sequences may also be used, as described in Table 11. The use ofcontinuous activating light sequences allows the lens curing equipmentto be simplified. For example, if continuous activating light is used,rather than pulsed light, equipment for generating light pulses is nolonger required. Thus, the cost of the lens curing apparatus may bereduced. Also the use of such a lens forming composition allows moregeneral curing processes to be used. As shown in Table 11, sevendifferent processes may be used to cure a wide variety of lenses. Thisgreatly simplifies the programming and operation of the lens curingunit.

Furthermore, the use a lens forming composition which includes anaromatic containing polyether polyethylenic functional monomer, aco-initiator composition and a photoinitiator may alleviate the need forcooling of the lens forming composition during curing. This may furthersimplify the procedure since cooling fans, or other cooling systems, mayno longer be required. Thus, the lens curing apparatus may be furthersimplified by removing the mold apparatus cooling systems.

Table 11 shows the preferable curing conditions for a variety of lenses.The sphere column refers to the sphere power of the lens. The monomertype is either clear (i.e., non-photochromic) or photochromic. Note thatthe lens type (e.g., spheric single vision, aspheric single vision lens,flat-top bifocal lens or progressive multifocal lens) does notsignificantly alter the lens curing conditions. Tinted refers to whetherthe formed eyeglass lens will be soaked in a dye bath or not.

Based on the prescription information the lens curing conditions may bedetermined. There are four curing variables to be set. The type of lightfilter refers to the filter placed between the lamps and the moldassembly in the curing unit and the post cure unit. The initial doesrefers to the time that activating light is applied to the lens formingcomposition in the curing unit. The irradiation pattern (e.g.,irradiation of the front mold only, the back mold only, or both molds)is also dependent on the lens being formed. After the initial dose isapplied the mold assembly is transferred to the post cure unit where itis treated with activating light and heat. The chart lists the preferredtime spent in the post cure chamber. After treatment in the post curechamber the formed eyeglass lens is removed from the mold assembly. Thelens may undergo an annealing process, for the time listed, in which thelens is heated either in the presence or absence of activating light. Itshould be noted that all of the lens curing processes recited arepreferably performed without any cooling of the mold apparatus.

To further illustrate this procedure, the method will be described indetail for the production of a clear, non-tinted lens having spherepower of +3.00. A mold assembly is filled with a non-photochromicmonomer solution. The mold assembly is placed in a lens curing unit toapply the initial dose to the lens forming composition. The curing ofthe lens forming composition is preferably controlled by controller 50.As shown in FIG. 17, the controller 50 includes a number of inputdevices which allow an operator to initiate use of the variouscomponents of the plastic lens curing apparatus 10. In an embodiment,buttons 640 may be used to control operation of the coating process (640a), the curing process (640 b), the postcure process (640 c), and theanneal process (640 d). After the mold assembly is placed in the lenscuring unit, the curing process button 640 b may be pressed to set thecuring conditions. In one embodiment, an operator has preloaded theprescription information and saved the information as described above.Pressing the cure button may cause the controller to prompt the user toenter a reference code corresponding to the saved prescriptioninformation. The controller is preferably configured to analyze theprescription information and set up the appropriate initial doseconditions.

After determining the appropriate lens forming conditions, thecontroller may inform the user of the type of filters to be used. Thecontroller may pause to allow the proper filters to be installed withinthe lens curing unit. Typically, two types of filters may be used forthe initial cure process. The filters are preferably configured todistribute the light so that the activating light which is imparted tothe lens molds is properly distributed with respect to the prescriptionof the lens. A clear plate filter refers to a plate that issubstantially transparent to activating light. The clear plate may becomposed of polycarbonate or glass. A 50 mm filter refers to filterwhich includes a 50 mm aperture positioned in a central portion of thefilter. The 50 mm aperture is preferably aligned with the mold assemblywhen the filter is placed in the curing unit. Preferably, two filtersare used, the first being placed between the top lamps and the moldassembly, the second being placed between the bottom lamps and the moldassembly.

After the filters have been placed, the user may indicate to thecontroller that the filters are in place. Alternatively, the controllermay include a sensor disposed within the lens curing unit which informsthe controller when a filter is placed within the curing unit. After thefilters are placed in the curing unit, the controller may prompt theuser to ensure that the mold assembly is in the curing unit prior tocommencing the curing process. When the filters and mold are in place,the initial dose may be started by the controller. For a clear,non-tinted lens having sphere power of +3.00 the initial dose will be 90seconds of activating light applied to both the front and back molds. A50 mm filter is preferably positioned between the top and bottom lamps.

After the initial cure process is completed, the mold assembly istransferred to the post cure unit. The completion of the initial cureprocess may cause the controller to alert the operator that the processis completed. An alarm may go off to indicate that the process iscompleted. To initiate the post cure process, the post cure button 640 cmay be pressed. Pressing the post cure button may cause the controllerto prompt the user to enter a reference code corresponding to the savedprescription information. The controller is preferably configured toanalyze the prescription information and set up the appropriate postcure conditions. For a clear, non-tinted lens having sphere power of+3.00 the post cure conditions will include directing activating lighttoward the mold assembly in a heated post cure unit for 13 minutes. Thepost cure unit is preferably heated to a temperature of about 200° F. toabout 225° F. during the post cure process.

After the post cure process is completed, the mold assembly isdisassembled and the formed lens is removed from the mold members. Thecompletion of the post cure process may cause the controller to alertthe operator that the process is completed. An alarm may go off toindicate that the process is completed. After the molds are removed fromthe post cure unit, the gasket is removed and the molds placed in ademolding solution. A demolding solution is commercially available as“Q-Soak Solution” commercially available from Optical DynamicsCorporation, Louisville, Ky. The demolding solution causes the lens toseparate from the molds. The demolding solution also aids in thesubsequent cleaning of the molds. After the lens has been demolded, thelens is preferably cleaned of dust particles using a solution ofisopropyl alcohol and water.

In some instances it is desirable that the formed lens undergoes ananneal process. To initiate the anneal process the anneal button 640 dmay be pressed. Pressing the anneal button will set the conditions forthe anneal process. For a clear, non-tinted lens having sphere power of+3.00 the anneal conditions will include heating the lens in the postcure unit, in the absence of activating light, for about 7 minutes. Thepost cure unit is preferably heated to a temperature of about 200° F. toabout 225° F. during the anneal process.

In one embodiment, the drawer of the post cure unit includes a front rowof mold assembly holders and a back row of lens holders. For the postcure process, the mold assemblies are preferably placed in the frontrow. The front row is preferably oriented under the post cure lamps whenthe post cure drawer is closed. For the anneal process the lenses arepreferably placed in the back row of the post-cure drawer. The back rowmay be misaligned with the lamps such that little or no activating lightreaches the back row.

After the anneal process, the lens may be coated in the coating unitwith a scratch resistant hard coat. The lens may also be tinted byplacing in a tinting bath. It is believed that tinting of the lens isinfluenced by the crosslink density of the lens. Typically, a lenshaving a relatively high crosslink density exhibits more homogenousabsorption of the dye. Problems such as blotching and streaking of thedye are typically minimized by highly crosslinked lenses. The crosslinkdensity of a lens is typically controlled by the temperature of curingof the lens. A lens which is cured at relatively high temperaturestypically exhibits a crosslink density that is substantially greaterthan a low temperature cured lens. The curing time may also influencethe hardness of a lens. Treating a lens for a long period of time in apost cure unit will typically produce a lens having a greater crosslinkdensity than lenses treated for a shorter amount of time. Thus, toproduce lenses which will be subsequently treated in a tinting bath, thelens forming composition is treated with heat and activating light inthe post cure unit for a longer period of time than for the productionof non-tinted lenses. As shown in table 11, non-tinted clear lenses aretreated in the postcure unit for about 13 minutes. For clear lenseswhich will be subsequently tinted, the post cure time is extended toabout 15 minutes, to produce a lens having a relatively high crosslinkdensity.

The formation of flat-top bifocal lenses may also be accomplished usingthe above described procedure. One problem typical of curing flat-topbifocal eyeglass lenses with activating light is premature release.Flat-top bifocals include a far vision correction zone and a near visioncorrection region. The far vision correction zone is the portion of thelens which allows the user to see far away objects more clearly. Thenear vision correction zone is the region that allows the user to seenearby objects clearer. The near vision correction zone is characterizedby a semicircular protrusion which extends out from the outer surface ofan eyeglass lens. As seen in FIG. 24, the portion of the mold cavitywhich defines the near vision correction zone 1610 is substantiallythicker than the portion of the mold cavity defining the far visioncorrection zone 1620. Directing activating light toward the mold memberscauses the polymerization of the lens forming composition to occur. Itis believed that the polymerization of the lens forming compositionbegins at the casting face of the irradiated mold and progresses throughthe mold cavity toward the opposite mold. For example, irradiation ofthe front mold 1630 causes the polymerization to begin at the castingsurface of the front mold 1632 and progress toward the back mold 1640.As the polymerization reaction progresses, the lens forming compositionis transformed from a liquid state to a gel state. Thus, shortly afterthe front mold 1632 is irradiated with activating light, the portion ofthe lens forming composition proximate the casting face of the frontmold member 1632 will become gelled while the portion of the lensforming composition proximate the back mold member 1640 will remainsubstantially liquid. If the polymerization is initiated from the backmold 1640, the lens forming composition throughout the far visioncorrection zone 1620 may become substantially gelled prior to gelationof the lens forming composition in the near vision correction zoneproximate the casting surface of the front mold member 1610 (hereinreferred to as the “front portion of the near vision correction zone”).It is believed that when the gelation of the lens forming composition inthe front portion of the near vision correction zone 1610 occurs afterthe far vision correction zone 1620 has substantially gelled, theresulting strain may cause premature release of the lens.

To reduce the incidence of premature release in flat-top bifocal lenses,it is preferred that polymerization of the lens forming composition inthe front portion of the near vision correction zone 1610 is initiatedbefore the portion of the lens forming composition in the far visioncorrection zone proximate the back mold member 1640 is substantiallygelled. Preferably, this may be achieved by irradiating the front mold1630 with activating light prior to irradiating the back mold 1640 withactivating light. This causes the polymerization reaction to beginproximate the front mold 1630 and progress toward the back mold 1640. Itis believed that irradiation in this manner causes the lens formingcomposition in the front portion of the near vision correction zone 1610to become gelled before the lens forming composition proximate the backmold 1640 becomes gelled. After the polymerization is initiated,activating light may be directed at either mold or both molds tocomplete the polymerization of the lens forming composition. Thesubsequent post cure and anneal steps for the production of flat-topbifocal lenses are substantially the same as described above.

Alternatively, the incidence of premature release may also be reduced ifthe front portion of the near vision correction zone 1610 is gelledbefore gelation of the lens forming composition extends from the backmold member 1640 to the front mold member 1630. In this embodiment, thepolymerization of the lens forming composition may be initiated byirradiation of the back mold 1640. This will cause the gelation to beginproximate the back mold 1640 and progress toward the front mold 1630. Toreduce the incidence of premature release, the front mold 1630 isirradiated with activating light before the gelation of the lens formingcomposition in the far vision correction zone 1620 reaches the frontmold. After the polymerization is initiated in the front portion of thenear vision correction zone 1610, activating light may be directed ateither mold or both molds to complete the polymerization of the lensforming composition. The subsequent post cure and anneal steps for theproduction of flat-top bifocal lenses are substantially the same asdescribed above.

In another embodiment, a single curing unit may be used to perform theinitial curing process, the post cure process, and the anneal process. Alens curing unit is depicted in FIG. 25 and FIG. 26. The curing unit1230 may include an upper light source 1214, a lens drawer assembly1216, and a lower light source 1218. Lens drawer assembly 1216preferably includes a mold assembly holder 1220 (see FIG. 26), morepreferably at least two mold assembly holders 1220. Each of the moldassembly holders 1220 is preferably configured to hold a pair of moldmembers that together with a gasket form a mold assembly. Preferably,the lens drawer assembly may also include a lens holder 1221 (see FIG.26), more preferably at least two lens holders 1221. The lens holders1221 are preferably configured to hold a formed eyeglass lens. The lensdrawer assembly 1216 is preferably slidingly mounted on a guide 1217.During use, mold assemblies and/or lenses may be placed in the moldassembly holders 1220 or lens holders 1221, respectively, while the lensdrawer assembly is in the open position (i.e., when the door extendsfrom the front of the lens curing unit). After the holders have beenloaded, the door may be slid into a closed position, with the moldassemblies directly under the upper light source 1214 and above thelower light source 1218. The lens holders and lenses disposed upon thelens holders may not be oriented directly under the upper and lowerlight sources. As depicted in FIG. 26, the light sources 1214 and 1218preferably extend across a front portion of the curing unit, while nolamps are placed in the rear portion of the curing unit. When the lensdrawer assembly is slid back into the curing unit, the mold assemblyholders 1220 are oriented under the lamps, while the lens holders 1221are oriented in the back portion where no lamps are present. Byorienting the holders in this manner curing process which involve lightand heat (e.g., post cure processes) and annealing processes, which mayinvolve either application of heat and light or the application of heatonly, may be performed in the same unit.

The light sources 1214 and 1218, preferably generate activating light.Light sources 1214 and 1218 may be supported by and electricallyconnected to suitable fixtures 1242. Lamps 1214 may generate eitherultraviolet light, actinic light, visible light, and/or infrared light.The choice of lamps is preferably based on the monomers andphotoinitiator system used in the lens forming composition. In oneembodiment, the activating light may be generated from a fluorescentlamp. The fluorescent lamp preferably has a strong emission spectra inthe 380 to 490 nm region. A fluorescent lamp emitting activating lightwith the described wavelengths is commercially available from Philips asmodel TID-15W/03. In another embodiment, the lamps may be ultravioletlights.

In one embodiment, an upper light filter 1254 may be positioned betweenupper light source 1214 and lens drawer assembly 1216, as depicted inFIG. 25. A lower light filter 1256 may be positioned between lower lightsource 1218 and lens drawer assembly 1216. Examples of suitable lightfilters have been previously described. The light filters are used tocreate a proper distribution of light with regard to the prescription ofthe eyeglass lens. The light filters may also insulate the lamps fromthe curing chamber. During post cure and annealing process it ispreferred that the chamber is heated to temperatures between about 200and 225° F. Such temperatures may have a detrimental effects on thelamps such as shortening the lifetime of the lamps and altering theintensity of the light being produced. The light filters 1254 and 1256,when mounted into the guide 1217, will form an inner chamber whichpartially insulates the lamps from the heated portion of the chamber. Inthis manner, the temperatures of the lamps may be maintained within theusual operating temperatures.

Alternatively, a heat barrier 1260 may be disposed within the curingchamber. The heat barrier may insulate the lamps from the curingchamber, while allowing the activated light generated by the lamps topass into the chamber. In one embodiment, the heat barrier may include aborosilicate plate of glass (e.g., PYREX glass) disposed between thelight sources and the mold assembly. In one embodiment, a pair ofborosilicate glass plates 1264 and 1262 with an intervening air gapbetween the plates 1263 serves as the heat barrier. The use ofborosilicate glass allows the activating radiation to pass from thelight sources to the lamps without any significant reduction intensity.

Along with the heat barrier 1260 and filter 1254, an opaque plate 1270,may be placed between the light sources and the mold assembly. Theopaque plate is substantially opaque toward the activating light.Apertures are preferably disposed in the opaque plate to allow light topass through the plate onto the mold assemblies.

In order to allow post cure and annealing procedures to be performed, aheating system 1250 is preferably disposed within the curing unit, asdepicted in FIG. 26. The heating system 1250 may be a resistive heatingsystem, a hot air system, or an infrared heating system. The heatingsystem 1250 may be oriented along the back side of the curing chamber.The heating system 1250 is preferably disposed at a position between thetwo filters, such that the heating system is partially insulated fromthe lamps 1214 and 1218. Preferably, the heating system is configured toheat the curing chamber to a temperature of about 200° F. to about 225°F.

The incorporation of a heating system into a system which allowsirradiation of a mold assembly from both sides will allow many of theabove described operations to be performed in a single curing unit. Theuse of lamps in the front portion of the curing unit, while leaving theback portion of the curing chamber substantially free of lamps, allowsboth activating light curing steps and annealing steps to performed inthe same unit at the same time. Thus the curing conditions described inTable 11 may be performed in a single unit, rather than the two units asdescribed above.

In another embodiment, the method of producing the lenses may bemodified such that all of the initial curing process is performed whileheat is applied to the lens forming composition. Table 12 showsalternate curing conditions which may be used to cure the lens formingcompositions.

TABLE 12 LENS INFORMATION CURING INFORMATION Sphere Lens Type TintedFilter Curing Conditions Anneal Time +4.00 to Clear No 50 mm 90 SecondsFront and Back 7 Min. +2.25 13 Minutes Back Temperature 225° F. +4.00 toClear Yes 50 mm 90 Seconds Front and Back 7 Min. +2.25 15 Minutes FrontTemperature 225° F. +4.00 to Photo 50 mm 90 Seconds Front and Back 7Min. +2.25 13 Minutes Front Temperature 225° F. +2.00 to Clear No ClearPlate 7 Seconds Front 7 Min. −4.00 13 Minutes Back Temperature 225° F.+2.00 to Clear Yes Clear Plate 7 Seconds Front 7 Min. −4.00 15 MinutesBack Temperature 225° F. +2.00 to Photo Clear Plate 15 Seconds Front 7Min. plano 13 Minutes Back Temperature 225° F. −0.25 to Photo ClearPlate 20 Seconds Back 7 Min. −4.00 w/ 7 Sec. Front starting @ 13 Sec.elapsed time 13 Minutes Back Temperature 225° F.

After the mold assembly is filled with the appropriate monomer solutionthe mold assemblies are placed in the mold assembly holders of thedrawer of the curing unit. The drawer is slid back into the curing unit.The curing unit may be preheated to a temperature of about 225° F. priorto placing the mold assemblies in the curing unit. The curing conditionsinclude applying activating light to one or both of the mold memberswhile substantially simultaneously applying heat to the mold assemblies.As shown in Table 12, the light curing conditions are similar to thepreviously described conditions. However, the initial dose and thepost-cure processes have been combined into a single process. Thus, forthe formation of a photochromic lens having a sphere power of +1.50, themold assemblies are placed in the lens curing unit and irradiated withactivating light from the bottom of the unit for about 15 seconds. Thecuring unit is preferably at a temperature of about 225° F. while theactivating light is applied. After 15 seconds, the bottom light isturned off and the mold assemblies are treated with activating lightfrom the top lamps for about 13 minutes. This subsequent treatment withactivating light is also performed at a curing chamber temperature ofabout 225° F. After the 13 minutes have elapsed, the lights may beturned off, the lens removed from the molds and an anneal process begun.

The anneal process may be performed in the same unit that the cureprocess is performed. The demolded lens is preferably placed in the lensholders of the curing unit drawer. The curing unit is preferably at atemperature of about 225° F., when the lens are placed in the curingunit. Preferably, the lens holders are positioned away from the lamps,such that little activating light reaches the lenses when the lamps areon. This allows anneal processed to be performed at the same time thatcuring processes are performed and within the same curing unit. Lensesthat have been formed with a mixture of heating and light typicallyexhibit crosslink density that are greater than lenses which are curedusing combinations of light only curing with light and heat curing.

The mold assembly, with a lens forming composition disposed within themold cavity, is preferably placed within the lens curing unit. Curing ofthe lens forming composition is preferably initiated by the controllerafter the lens curing unit door is closed. The curing conditions arepreferably set by the controller based on the prescription and type oflens being formed.

After the curing cycle has been completed. The controller preferablyprompts the user to remove the mold assembly from the lens curing unit.In an embodiment, the cured lens may be removed from the mold apparatus.The cured lens may be complete at this stage and ready for use.

In another embodiment, the cured lens may require a post cure treatment.After the lens is removed from the mold apparatus the edges of the lensmay be dried and scraped to remove any uncured lens forming compositionnear the edges. The controller may prompt the user to place thepartially cured lens into a post-cure unit. After the lens has beenplaced within the post-cure unit the controller may apply light and/orheat to the lens to complete the curing of the lens. In an embodiment,partially cured lenses may be heated to about 115° C. while beingirradiated with activating light. This post-treatment may be applied forabout 5 minutes.

It has been determined that in some embodiments the finished power of anactivating light polymerized lens may be controlled by manipulating thecuring temperature of the lens forming composition. For instance, for anidentical combination of mold members and gasket, the focusing power ofthe produced lens may be increased or decreased by changing theintensity of activating light across the lens mold cavity or the facesof the opposed mold members. Methods for altering the power of a formedlens are described in U.S. Pat. No. 5,989,462 to Buazza which isincorporated by reference.

In certain applications, all of the lens forming composition may fail tocompletely cure by exposure to activating light when forming the lens.In particular, a portion of the lens forming composition proximate thegasket often remains in a liquid state following formation of the lens.It is believed that the gaskets may be often somewhat permeable to air,and, as a result, oxygen permeates them and contacts the portions of thelens forming material that are proximate the gasket. Since oxygen tendsto inhibit the polymerization process, portions of the lens formingcomposition proximate the gasket tend to remain uncured as the lens isformed. The wet edge problem has been addressed by a variety of methodsdescribed in U.S. Pat. No. 5,529,728 to Buazza et. al. and U.S. Pat. No.5,989,462 to Buazza et al. which are incorporated by reference.

Methods for curing a lens forming composition by the use of pulses ofultraviolet light are described in U.S. Pat. No. 6,022,498 which isincorporated by reference.

Materials (hereinafter referred to as “activating light absorbingcompounds”) that absorb various degrees of ultraviolet/visible light maybe used in an eyeglass lens to inhibit ultraviolet/visible light frombeing transmitted through the eyeglass lens. Such an eyeglass lensadvantageously inhibits ultraviolet/visible light from being transmittedto the eye of a user wearing the lens. Curing of an eyeglass lens usingactivating light to initiate the polymerization of a lens formingcomposition that includes activating light absorbing compositions isdescribed in detail in U.S. Pat. No. 5,989,462 which is incorporated byreference.

Referring now to FIG. 27, a high-volume lens curing apparatus isgenerally indicated by reference numeral 800. As shown in FIG. 27, lensforming apparatus 800 includes at least a first lens curing unit 810 anda second lens curing unit 820. The lens forming apparatus may,optionally, include an anneal unit 830. In other embodiments, a postcure unit may be a separate apparatus which is not an integral part ofthe lens curing apparatus. A conveyance system 850 may be positionedwithin the first and/or second lens curing units. The conveyance system850 may be configured to allow a mold assembly, such as has beendescribed above, to be transported from the first lens curing unit 810to the second lens curing unit 820.

Lens curing units 810 and 820 include an activating light source forproducing activating light. The activating light sources disposed inunits 810 and 820 are preferably configured to direct light toward amold assembly. Anneal unit 830 may be configured to apply heat to an atleast partially relive or relax the stresses caused during thepolymerization of the lens forming material. Anneal unit 830, in oneembodiment, includes a heat source. A controller 840 may be aprogrammable logic controller, e.g., a computer. Controller 840 may becoupled to lens curing units 810 and 820 and, if present, an anneal unit830, such that the controller is capable of substantially simultaneouslyoperating the three units 810, 820, and 830.

As shown in FIG. 28, the first curing unit 810 may include an upperlight source 812 and a lower light source 814. FIG. 29 depicts a cutaway top view of the first curing unit 810. As shown in FIG. 29 thelight sources 812 and 814 of the first curing unit 810 may include aplurality of activating light generating devices or lamps. In oneembodiment, the lamps are oriented proximate each other to form a row oflights, as depicted in FIG. 29. While the lamps are depicted assubstantially U-shaped, it should be understood that the lamps may belinear, circular, or any other shape that allows a uniform irradiationof a lens forming assembly placed in the first curing unit. In oneembodiment, three or four lamps are positioned to provide substantiallyuniform radiation over the entire surface of the mold assembly to becured. The lamps may generate activating light.

The lamps may be supported by and electrically connected to suitablefixtures 811. Lamps 812 and 114 may generate either ultraviolet light,actinic light, visible light, and/or infrared light. The choice of lampsis preferably based on the monomers used in the lens formingcomposition. In one embodiment, the activating light may be generatedfrom a fluorescent lamp. The fluorescent lamp preferably has a strongemission spectra in the 380 to 490 nm region. A fluorescent lampemitting activating light with the described wavelengths is commerciallyavailable as model number FB290D15/ACT/2PC from LCD Lighting, Inc. inOrange Conn.

In some embodiments, the activating light sources may be turned on andoff frequently during use. Fixture 811 may also include electronichardware to allow a fluorescent lamp to be frequently turned on and off.Ballasts systems, such as the ones previously described, may be used tooperate the lamps. In some embodiments, a barrier 815 may be placedbetween the lamps 811. The barrier may be configured to inhibit thepassage of activating light from one set of lamps to the other. In thismanner, the lamp sets may be optically isolated from each other. Thelamps may be connected to separate ballast systems and a controller.Thus, the lamps may be operated independently of each other. This may beuseful when lenses that require different initial curing sequences arebeing processed at the same time. The barrier 815 may inhibit thepassage of light from one set of lamps to a mold assembly positionedbelow the other set of lamps.

In some embodiments, at least four independently controllable lamps orsets of lamps may be disposed in the first curing unit. The lamps may bedisposed in left and right top positions and left and right bottompositions. As shown in Table 12, a variety of different initial curingconditions may be required depending on the prescription. In someinstances the left eyeglass lens may require initial curing conditionsthat are substantially different from the initial curing conditions ofthe right eyeglass lens. To allow both lenses to be cured substantiallysimultaneously, the four sets of lamps may be independently controlled.For example, the right set of lamps may be activated to apply light tothe back face of the mold assembly only, while, at the same time, theleft set of lamps may be activated to apply light to both sides of themold assembly. In this manner a pair of eyeglass lenses whose left andright eyeglass prescriptions require different initial curing conditionsmay be cured at substantially the same time. Since the lenses may thusadvantageously remain together in the same mold assembly holderthroughout the process, the production process is simpler with minimizedjob tracking and handling requirements.

To facilitate the positioning and the conveyance of mold assemblies, amold assembly holder may be used. An isometric view of a mold assemblyholder 900 is depicted in FIG. 30. The mold assembly holder includes atleast one, preferably two, portions 910 and 912 configured to hold amold assembly 930. In one embodiment, the portions 910 and 912 areindentations machined into a plastic or metal block that is configuredto hold a standard mold assembly. The mold assembly may be placed in theindentation. An advantage of such the indentations, is that the moldassemblies may be positioned in the optimal location for curing in thefirst and second curing units 810 and 820.

The indentations 910 and 912 may be sized to hold the mold assembly suchthat substantially all of the molds may be exposed to activating lightwhen the mold assembly is positioned above or below an activating lightsource. The mold assembly holder may include an opening extendingthrough the mold assembly holder. The opening may be positioned in theindentations 910 and 912 such that activating light may be shone throughthe mold assembly holder to the mold assembly. In some embodiments, theopening may be of a diameter that is substantially equal to the diameterof the molds. The opening will therefore allow substantially all of thesurface area of the mold to be irradiated with activated light. Inanother embodiment, the diameter of the opening may be substantiallyless than a diameter of the molds. In this respect the opening may serveas an aperture which reduces the amount of light that contacts the outeredges of the molds. This may be particularly useful for curing positivelenses in which curing is initiated with more activating light beingapplied to the central portion of the molds than the edges. Theindentations may extend in the body to a depth such that the moldassemblies, when placed in the indentations is even with or below theupper surface of the mold assembly holder. This imparts a low verticalprofile to the mold assembly holder and allows the curing units of thehigh volume system to be constructed with a low vertical profile. Inthis manner the size of the unit may be minimized.

The mold assembly holder 900 may also include further machinedindentations for holding the unassembled pieces of the mold assembly(e.g., the molds and the gasket). During the assembly of the moldassembly, an operator typically will find and clean the molds and gasketbefore assembly. To minimize the possibility of mixing up the molds andgaskets, and to help minimize recontamination after the molds arecleaned, the mold assembly holder 900 includes sections to hold thevarious components. As depicted in FIG. 30, indentations 922, 924, 926,and 928 may also be formed in the mold assembly holder 900. Theindentations may be labeled to facilitate the placement of the molds orgaskets. For example, indentation 922 may be labeled left lens, frontmold, 924 may be labeled left lens, back mold, 928 may be labeled rightlens, front mold, and 926 may be labeled right lens, back mold. Othervariations of labeling and positioning of the indentations 922, 924,926, and 928 may be used. This may help prevent operators from makingmistakes due to use of incorrect molds to assemble the mold assemblies.

The mold assembly holder may also include a location for holding a jobticket. Job ticket may be placed in a holder mounted to a side of themold assembly holder. Alternatively, the job ticket may have an adhesivethat allows the ticket to be attached to the side of the mold assembly.The job ticket may include information such as: the prescriptioninformation, the mold ID numbers, the gasket ID numbers, the time, date,and type of lens being formed. The job ticket may also include a jobnumber, the job number may correspond to a job number generated by thecontroller when the prescription is entered into the controller. The jobnumber may also be depicted using a UPC coding scheme. Use of a UPC codeon the job ticket may allow the use of bar-code scanners to determinethe job number corresponding to the mold assemblies placed on the moldassembly holder.

The mold assembly holder 900 may be used in combination with a conveyorsystem 850 to transfer mold assemblies from the first curing unit to thesecond curing unit. The second curing unit is configured to applyactivating light and heat to the mold assemblies after the curing isinitiated by the first curing unit. The use of two curing units in thismanner facilitates the application of curing sequences such as thesequences outlined in Table 11. In these embodiments, the mold assemblyis subjected to an initiating dose of activating light, followed by apost-cure dose of activating light and heat. The initial dose may lastfrom about 7 to 90 seconds. After the initial dose is applied the moldassembly is subjected to a combination of activating light and heat forabout 5 to 15 minutes. In many instances, subjecting the mold assemblyto longer times under the post-cure conditions does not significantlyeffect the quality of the formed lens. Thus, the second curing unit isdesigned such that the amount of time that the mold assemblies spend inthe second unit is not less than about 5 minutes.

During operation a mold assembly or mold assembly holder is placed onthe conveyor system and the mold assembly is moved to a position withinthe first curing unit 810. In the first curing unit 810, the moldassemblies receive the initial dose of light based on the prescriptionof the lens, e.g., as outlined in Table 11. After the mold assembliesreceive their initial dose, the mold assemblies are moved by theconveyor system 850 to the second curing unit. In the second curingunit, the mold assemblies are treated with activating light and heat.The time it takes for the mold assembly to pass entirely through thesecond curing unit may be equal to or greater than the post-cure time.

In one embodiment, the conveyor system may be a single continuous systemextending from the first curing unit through the second curing unit.During the operation of the lens forming apparatus 800, it is envisionedthat a continuous stream of mold assemblies may be placed on theapparatus. FIG. 32 depicts a top cut away of a system in which acontinuous stream of mold assembly holders 900 are moving through thefirst and second curing units. Because the curing for any givenprescription lens is complete in the first curing unit in a time of 90seconds or less, the second unit may be constructed as a rectangularshaped unit that will hold multiple mold assemblies, as depicted in FIG.27. The length of the second cure unit is determined by the timerequired for each mold assembly in the first unit. Because the conveyorsystem is a single continuous unit, the molds will move through thesecond curing unit in increments equal to the amount of time spent inthe first curing unit. Thus, the molds move only when the curing cycleof the first curing unit is complete and the mold assemblies or moldassembly holder is advanced to the second curing unit.

In one embodiment, the mold assemblies are placed on a mold assemblyholder 900 as described above. The mold assembly holder may have apredetermined length (L_(H)). After the mold assemblies are loaded ontothe mold assembly holder, the mold assembly holder may be placed on theconveyor system 850 and advanced to the first curing unit. The moldassembly holder will remain in the first curing unit for a predeterminedminimum amount of time, i.e., the initiation time (T₁). For example, formost of the lens forming compositions and prescriptions outlined above,this maximum time will be about 90 sec. After the initial cure isperformed, the mold assembly holder is advanced to the second curingunit and another mold assembly holder is advanced to the first curingunit. To properly cure lens forming composition, the mold assemblies mayneed to remain in the second curing unit for a minimum amount of time,i.e., the post-cure time (T_(P)). The required minimum length of thesecond curing unit (L_(SC)) may, therefore be calculated by thesepredetermined values using the following equation.

L_(SC)=L_(H)×(T_(P)/T_(I))

By constructing the second curing unit to have a length based on thisequation, the mold assembly holder will exit from the second curing unitafter the correct amount of post-curing has occurred. This will ensurethat the mold assembly will remain in a post-cure situation even if theminimal initiation times are used.

In practice there is a wide variation in the initiation times based onthe prescription and the type of lenses being formed. For example, Table11 discloses some typical initiation times that range from about 7 sec.to about 90 sec. In order to optimize the system, the length of thesecond curing unit may be altered based on the maximum predeterminedinitiation time. For example, the (T_(I)) rather than being the minimumtime will be the maximum time possible for initiation of the curing. Inpractice, the conveyor system may be configure to advance a moldassembly holder from the first curing unit to the second curing unit attime intervals equal to the maximum possible initial curing cycle (e.g.,about 90 sec. for the above-described compositions) To accommodate thedifferent initial curing cycles, a controller may be coupled to thelamps of the first curing unit. The controller may be configured to turnon the lamps such that the initial curing cycle ends at the end of themaximum initial curing time. For example, if the maximum initial curingtime is 90 sec., however the prescription and lens type calls for only a7 sec, cure. The lamps are kept off until 7 sec. before the end of the90 sec. time interval (i.e., for 83 seconds). The lamps are, therefore,only activated for the last 7 sec. This may ensure that the timeinterval between the end of the completion of the initial cure and theentry into the second curing unit is the same regardless of the actualinitiation dosage. The length of the second curing unit may be adjustedaccordingly to accommodate this type of curing sequence.

In another embodiment, the conveyor system may include two independentlyoperated conveyors. The first conveyor may be configured to convey themold assembly holder or mold assemblies from the first curing unit tothe second curing unit. A second conveyor may be positioned within thesecond curing unit. The second conveyor may be configured to convey themold assemblies or the mold assembly holder through the second curingunit. In this manner the second curing unit may be designedindependently of the initial curing times. Instead the length of thesecond curing unit may be based on the time required for a typicalpost-cure sequence. Thus the length of the second curing unit may bedetermined by the rate at which the second conveyor system is operatedand the amount of time required for a post-cure. This also allows anoperator to operate the curing units independently of the other.

The conveyor system may be configured to convey either mold assembliesor a mold assembly holder (e.g., mold assembly holder 900 ) through thefirst and second curing units. A view of the conveyor system in whichthe curing units have been removed from the lens forming apparatus isdepicted in FIG. 31. The conveyor system includes a platform forconveying a mold assembly holder. The platform may be configured tosupport the mold assembly holder 900 as it passes through the first andsecond curing units. In one embodiment, the platform is formed from tworails 852 that extend the length of the lens forming apparatus. Therails, 852 may be any width, however should be spaced apart from eachother at a distance that allows activating light to pass past the rails852 and to the mold assemblies on the mold assembly holder 900.

The conveyor system includes a flexible member 854 (e.g., a belt orchain) that is configured to interact with the mold assembly holder 900.The flexible member will interact with the mold assembly holder and pullor push the mold assembly holder along the platform. FIG. 33 depicts aclose up view of a portion of the flexible member. In this embodiment,the flexible member is composed of a chain 854 that includes a number ofprojections 856 and 858 that are placed at predetermined positions alongthe chain. The projections may be configured to interact with the moldassembly holder. In one embodiment, the mold assembly holder may includea ridge along the bottom surface. The ridge will interact with theprojections when the chain is moved to the appropriate position. Whiledepicted as a chain, it should be understood that the flexible membermay be formed of other materials such as a rubber belt.

The flexible member 854 may be coupled to a pair of wheels or gearsdisposed at opposite ends of the lens forming apparatus. FIG. 33 depictsa portion of the flexible member that is resting on a gear disposed atan end of the lens forming apparatus. The flexible member may be movedalong the lens forming apparatus by turning either of the wheels orgears. The wheels or gears may be manually turned or may be coupled to amotor. FIG. 34 depicts a lens forming apparatus in which a motor 851 iscoupled to an end of the second curing unit. The motor may be coupled tothe flexible member such that the flexible member may be moved by theoperation of the motor. The motor 851 may either pull or push theflexible member along the length of the lens forming apparatus.

The second curing unit may be configured to apply heat and activatinglight to a mold assembly as it passes through the second curing unit.The second curing unit may be configured to apply activating light tothe top, bottom, or both top and bottom of the mold assemblies. Asdepicted in FIGS. 28 and 35, the second curing unit may include a bankof activating light producing lamps 822 and heating systems 824. Thebank of lamps may include one or more substantially straight fluorescentlamps that extend through the entire length of the second curing unit.The activating light sources in the second curing unit may produce lighthaving the same spectral output as the activating light sources in thefirst curing unit. The spectral output refers to the wavelength range oflight produced by a lamp, and the relative intensity of the light at thespecific wavelengths produced. Alternatively, a series of smaller lampsmay be disposed with the curing unit. In either case, the lamps arepositioned such that the mold assemblies will receive activating lightas they pass through the second curing unit. The heating unit may be aresistive heater, hot air system, hot water systems, or infrared heatingsystems. An air distributor 826 (e.g., a fan) may be disposed within theheating system to aid in air circulation within the second curing unit.By circulating the air within the second curing unit, the temperaturewithin the second curing may be more homogenous.

In some embodiments, an anneal unit may also be coupled to the lensforming apparatus. As depicted in FIG. 27, an anneal unit 830 may beplaced above the second curing unit. Alternatively, the anneal unit maybe placed below or alongside of the first or second curing units. Theanneal unit is configured to apply heat and, optionally light, to anneala demolded lens. When a lens, cured by the activating light, is removedfrom a mold assembly, the lens may be under a stressed condition. It isbelieved that the power of the lens can be more rapidly brought to afinal resting power by subjecting the lens to an anneal treatment torelieve the internal stresses developed during the cure. Prior toannealing, the lens may have a power that differs from the desired finalresting power. The anneal treatment is believed to reduce stress in thelens, thus altering the power of the lens to the desired final restingpower. Preferably, the anneal treatment involves heating the lens at atemperature between about 200° F. to 225° F. for a period of up to about10 minutes. It should be understood that the anneal time may be varieddepending on the temperature of the anneal unit. Generally, the higherthe temperature of the anneal unit, the faster the anneal process willbe completed. The anneal process time is predetermined based on theamount of time, at a predetermined temperature, a formed lens will needto be annealed to be brought to its final resting power.

In the embodiment depicted in FIG. 27, the anneal unit may beconstructed in a similar manner to the second curing unit. Turning toFIG. 35, the anneal unit may include a conveyor system 832 for moving ademolded lens through the anneal unit. The demolded lens may be placedin the same mold assembly holder that was used for the first and secondcuring units. The mold assembly holder 900 may be configured to holdeither the mold assembly and/or a demolded lens. The anneal unitincludes a heating element 834 (depicted in FIG. 28). The heatingelement may include a air distributor 836 for circulating air throughoutthe anneal unit.

The anneal unit may have a length that is determined by the rate atwhich the mold assembly holders are transported through the anneal unitand the time required for the anneal process. For example, in some ofthe compositions listed above, an anneal time of about 10 min. may beused to bring the lens to its final resting power. The conveyor systemof the anneal unit may therefore be configured such that the demoldedlenses spend about 10 minutes within the anneal unit as the lensestraverse the length of the unit. A conveyor system similar to the systemdescribed above for the first and second curing units may be used.

The controller 840 may be configured to control operation of thelens-curing units. The controller may perform some and/or all of anumber of functions during the lens curing process, including, but notlimited to: (i) determining the initial dose of light required for thefirst curing unit based on the prescription; (ii) applying theactivating light with an intensity and duration sufficient to equal thedetermined dose; (iii) applying the activating light with an intensityand duration sufficient to equal the determined second curing unit dose;(iv) turning the lamps sources on and off independently and at theappropriate times; and (v) triggering the movement of the proper lightfilters into the proper position based on the prescription. Thesefunctions may be performed in response to information read by the barcode reader from the job ticket positioned on the mold assembly holder.This information may include the prescription information and may becorrelated with the initial curing conditions by the controller 840.

The controller may also control the flow of the mold assembly holderthrough the system. The controller may include a monitoring device fordetermining the job number associated with a mold assembly holder. FIG.29 depicts a monitoring device 817 which is coupled to the lens formingapparatus proximate the first curing unit. The monitoring device may bea laser or infra-red reading device. In some embodiments, the monitoringdevice may be a bar code reader for reading a UPC bar code. Themonitoring device may be positioned within the first curing unit. When amold assembly holder is placed on the conveyer system, it may be movedto a position such that the monitoring device may read a job numberprinted on the job ticket. In one embodiment, the job number is in theform of a UPC bar code. The monitoring device may be coupled to thecontroller. The controller may use the job number, read from the moldassembly holder, to determine the curing conditions required for the jobthat is being transferred to the first curing unit. As described before,the job number may correspond to a prescription that was previouslyentered into the controller. In this manner the proper curing conditionsmay be achieved without relying on the operator to input the correctparameters.

Another advantage of the monitoring of the job number is that accidentalusage of the lamps may be avoided. If the monitoring device ispositioned within the first cure unit, the controller may prevent theactivation of the first cure unit lamps, until a job ticket is detected.The detection of a job ticket may indicate that a mold assembly holderis placed in the proper position within the first curing unit. Once themold assembly holder is placed within the first curing unit, the lampsof the first curing unit may be activated to initiate curing. If no jobticket is detected, the apparatus may wait in a stand-by mode until themold assembly holder is inserted into the first curing unit.

It should be understood, that the above-described lens curing system maybe used in combination with any of the features of the previouslydescribed embodiments.

Antireflective Coatings for Plastic Eyeglass Lenses

For plastic eyeglass lenses, formed from the materials described above,a portion of the light incident upon the lenses may be reflected fromthe eyeglass lens rather than transmitted through the eyeglass lens. Forplastic eyeglass lenses up to about 15% of the incident light may bereflected off the eyeglass lens surfaces. To reduce the reflection oflight from a plastic eyeglass lens, a thin film may be applied to thelens. Such films may be referred to as antireflective coating films.Antireflective coatings may reduce the reflectance of light from asurface (i.e., increase light transmittance through the film/substrateinterface).

While numerous approaches to reducing the reflective losses for glassmaterials have been developed, few techniques are available forproducing antireflective coatings on plastics. Vapor depositiontechniques have been used commercially to form antireflective coatingson plastic materials, however these techniques suffer from a number ofdrawbacks. Some of the disadvantages of using vapor deposition includerelatively large capital expenditure for deposition equipment,significant space requirements, and relatively long cycle times.

Reactive liquid compositions for forming antireflective coatings onlenses have been previously studied. Many of the previously disclosedsolutions require heating of the antireflective film to a hightemperature after its application to a substrate. In some instances thetemperature to cure such solutions may be greater than about 200° C.Such temperatures may be suitable for the coating of glass substrates,but are higher than most plastic lens substrates are capable ofwithstanding.

U.S. Pat. Nos. 4,929,278 and 4,966,812 describe a process for depositingantireflective films on a plastic substrate by first synthesizing anethanol gel in a SiO₂—B₂O₃—Al₂O₃—BaO system followed by reliquifying thegel. This material may be applied to a plastic substrate and thermallydried to form a porous film having a low refractive index. Such films,however, may exhibit poor abrasion resistance and can take weeks toform.

U.S. Pat. Nos. 5,580,819 and 5,744,243 disclose a composition forproducing coatings and a process for preparing single-layer broad bandantireflective coatings on a solid substrate, such as glass, ceramics,metals and organic polymeric materials. The process involves applying anacid-catalyzed sol-gel coating composition and a water soluble metalsalt to the surface of a solid substrate and curing the applied coatingwith an aqueous electrolyte solution for a time sufficient to produce acoating. The two step preparation of the coating composition, however,may be time consuming since the treatment with the aqueous electrolytemay take several days.

The use of ultraviolet light curable liquid compositions for formingantireflective coatings on substrates offers a number of advantages overthe deposition techniques described above. In particular, the equipmentcost tends to be minimal and the application techniques tend to minimizealterations to the shape or clarity of the plastic item being coated.Additionally, the liquid compositions of the present invention, may becured in a time of less than about 10 minutes. Finally, the liquidcompositions, of the present invention, may be applied to a variety ofvisible light transmitting substrates. Such substrates may be composedof glass or plastic. It should be understood that the liquidcompositions for forming an antireflective coating described herein maybe applied to a number of visible light transmitting substratesincluding windows and the outer glass surface of television screens andcomputer monitors. The liquid composition may be used to form anantireflective coating on a lens, preferably on plastic lenses, and morepreferably on plastic eyeglass lenses.

In an embodiment, a single layer coating may be formed on a plastic lensby coating the substrate with an ultraviolet light curable liquidcomposition and curing the composition. While the below describedprocedures refer to the coating of plastic lenses, it should beunderstood that the procedures may be adapted to coat any of the abovedescribed substrates. The cured composition may form a thin layer (e.g.,less than about 500 nm) on the substrate. The cured composition layermay have antireflective properties if the thin layer has an index ofrefraction that is less than the index of refraction of the substrate.This may be sufficient for many applications where a limited increase invisible light transmission is acceptable. Single layer antireflectivecoatings, however, may exhibit poor adhesion to the plastic lens.Attempts to increase the adhesion to the plastic lens by altering thecomposition, may cause the index of refraction of the single layerantireflective coating to increase and reduce the effectiveness of suchlayers.

Better antireflective properties and adhesion may be achieved by use ofmulti-layer antireflective coatings. In one embodiment, a two layerstack of coating layers may be used as an anti-reflective coating. Afirst coating layer may be formed on the surface of a plastic lens. Thefirst coating layer may be formed by dispensing a first composition onthe surface of the lens and subsequently curing the first composition.The first coating layer may be formed from a material that has an indexof refraction that is greater than the index of refraction of theplastic lens. A second coating layer may be formed upon the firstcoating layer. The second coating layer may be formed by dispensing asecond composition onto the first coating layer and curing the secondcomposition. The second coating layer may be formed from a material thathas an index of refraction that is less than the index of refraction ofthe first coating layer. Together the first coating layer and the secondcoating layer form a stack that may act as an antireflective coating.The first and second coating layers, together, may form a stack having athickness of less than about 500 nm.

In one embodiment, the first coating layer may be formed from a coatingcomposition that includes a metal alkoxide or a mixture of metalalkoxides. Metal alkoxides have the general formula M (Y)_(p) wherein Mis titanium, aluminum, zirconium, boron, tin, indium, antimony, or zinc,Y is a C₁-C₁₀ alkoxy or acetylacetonate, and p is an integer equivalentto the valence of M. In some embodiments, M is titanium, aluminum,boron, or zirconium, and Y is C₁-C₅ alkoxy (e.g., methoxy or ethoxy).Examples of metal alkoxides include, but are not limited to aluminumtri-sec-butoxide, titanium (IV) isopropoxide, titanium (IV) butoxide,zirconium (IV) propoxide, titanium allylacetoacetate triisopropoxide,and trimethyl borate. The first coating layer may be formed by using asol-gel (i.e., solution-gelation) process. Metal alkoxides, when reactedwith water or an alcohol, undergo hydrolysis and condensation reactionsto form a polymer network. As the polymer network is formed the solventmay be expelled. The polymer network will continue to grow until a gelis formed. Upon heating or the application of ultraviolet light, themetal alkoxide gel densifies to become a hardened coating on the plasticlens.

The hardened first coating layer, when formed from a sol-gel reaction ofa metal alkoxide may have an index of refraction that is greater thanthe plastic lens. For example, most plastic lenses have an index ofrefraction from about 1.5 to about 1.7. The first coating layer may havean index of refraction that is greater than 1.7 when formed from a metalalkoxide. The use of metal alkoxides has the advantage of allowing ahigh index of refraction coating on the surface of the lens. Anotheradvantage attained from the use of metal alkoxides is increased adhesionto the underlying substrate. A general problem for many antireflectivecoatings is poor adhesion to the underlying substrate. This isparticularly true for coatings formed on plastic substrates, althoughadhesion may also be a problem for glass substrates. The use of metalalkoxides increases the adhesion of the coating material to both plasticand glass substrates. The use of metal alkoxides, therefore, increasesthe durability of the antireflective coating.

The metal alkoxide may be dissolved or suspended in an organic solventand subsequently applied to a plastic lens. The coating composition mayinclude a metal alkoxide dissolved or suspended in an organic solvent.The coating composition may include up to about 10% by weight of a metalalkoxide with the remainder of the composition being composed of theorganic solvent and other additive compounds described below. In oneembodiment, suitable organic solvents are capable of mixing with waterand are substantially unreactive toward the metal alkoxide. Examples ofsuch solvents include, but are not limited to ethyl acetate, ethers(e.g., tetrahydrofuran and dioxane), C₁-C₆ alkanol (e.g., methanol,ethanol, 1-propanol, and 2-propanol), alkoxyalcohols (e.g.,2-ethoxyethanol-2-(2-methoxyethoxy) ethanol, 2-methoxyethanol,2-(2-ethoxymethoxy) ethanol, and 1-methoxy-2-propanol), ketones (e.g.,acetone, methyl ethyl ketone, and methyl isobutyl ketones, or mixturesof any of these compounds.

In another embodiment, the first composition may include a silanemonomer. Silane monomers have the general structure R_(m)SiX_(4−m),where R may be C₁-C₂₀ alkyl, C₁-C₂₀ haloalkyl, C₂-C₂₀ alkenyl, C₂-C₂₀haloalkenyl, phenyl, phenyl(C₁-C₂₀)alkyl, C₁-C₂₀ alkylphenyl, phenyl(C₂-C₂₀)alkenyl, C₂-C₂₀ alkenylphenyl, glycidoxy (C₁-C₂₀) alkyl,epoxycyclohexyl(C₁-C₂₀)alkyl, morpholino, amino(C₁-C₂₀)alkyl,amino(C₂-C₂₀)alkenyl, mercapto(C₁-C₂₀)alkyl, mercapto(C₂-C₂₀)alkenyl,cyano(C₁-C₂₀) alkyl, cyano(C₂-C₂₀)alkenyl, acryloxy, methacryloxy, orhalogen. The halo or halogen substituents may be bromo, chloro, orfluoro. Preferably, R¹ is a C₁-C₁₀ alkyl, C₁-C₁₀ haloalkyl, C₂-C₁₀alkenyl, phenyl, phenyl(C₁-C₁₀)alkyl, C₁-C₁₀ alkylphenyl,glycidoxy(C₁-C₁₀)alkyl, epoxycyclohexyl(C₁-C₁₀)alkyl, morpholino,amino(C₁-C₁₀)alkyl, amino(C₂-C₁₀)alkenyl, mercapto(C₁-C₁₀)alkyl,mercapto(C₂-C₁₀) alkenyl, cyano(C₁-C₁₀) alkyl, cyano(C₂-C₁₀)alkenyl, orhalogen and the halo or halogen is chloro or fluoro. X may be hydrogen,halogen, hydroxy, C₁-C₅ alkoxy, (C₁-C₅)alkoxy(C₁-C₅)alkoxy, C₁-C₄acyloxy, phenoxy, C₁-C₃ alkylphenoxy, or C₁-C₃ alkoxyphenoxy, said haloor halogen being bromo, chloro or fluoro; m is an integer from 0 to 3.The first coating composition may include up to about 5% by weight of asilane monomer. p Examples of silane monomers include, but are notlimited to glycidoxymethyltriethoxysilane,α-glycidoxyethyltrimethoxysilane, α-glycidoxyethyltriethoxysilane,β-glycidoxyethyltrimethoxysilane, β-glycidoxyethyltriethoxysilane,α-glycidoxypropyltrimethoxysilane, α-glycidoxypropyltriethoxysilane,β-glycidoxypropyltrimethoxysilane, β-glycidoxypropyltriethoxysilane,γ-glycidoxypropyltrimethoxysilane,γ-glycidoxypropylmethyldimethoxysilane,γ-glycidoxypropyldimethylethoxysilane, methyltrimethoxysilane,methyltriethoxysilane, methyltrimethoxyethoxysilane,methyltriacetoxysilane, methyltripropoxysilane, methyltributoxysilane,ethyltrimethoxysilane, ethyltriethoxysilane,γ-methacryloxypropyltrimethoxysilane, γ-aminopropyltrimethoxysilane,γ-aminopropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane,chloromethyltrimethoxysilane, chloromethytriethoxysilane,dimethyldiethoxysilane, γ-chloropropylmethyldimethoxysilane,γ-chloropropyl methyldiethoxysilane, tetramethylorthosilicate,tetraethylorthosilicate, hydrolyzates of such silane monomers, andmixtures of such silane monomers and hydrolyzates thereof.

Silane monomers, along with colloidal silica, may form low index ofrefraction silicon-based coatings. In some instances, silane monomersand colloidal silica may be used to form a single layer low index ofrefraction coating layer on a lens. The use of silicon monomers andcolloidal silica, however, tends to produce silicon-based coatings thathave poor adhesion to the underlying substrate. The addition of a metalalkoxide to a composition that also contains a silane monomer orcolloidal silica may improve the adhesion of the layer. In anotherembodiment, the adhesion of a silicon-based coating may be improved bythe formation of a multi-layer stack. The stack may include a firstcoating layer which is formed from a metal alkoxide. A second layer maybe formed upon the first layer, the second layer being formed from asilane monomer or colloidal silicon. The metal alkoxide based firstlayer acts as an adhesion layer that helps keep the stack bound to theunderlying lens.

In addition the silane monomers and colloidal silica may be mixed withmetal alkoxides to alter the index of refraction of the coatingcomposition. Typically, a mixture of a silane monomer with a metalalkoxide when cured onto a lens, will have a lower index of refractionthan a coating formed from a metal alkoxide.

In some embodiments, one or more ethylenically substituted monomers maybe added to the first composition. The ethylenically substituted groupof monomers include, but are not limited to, C₁-C₂₀ alkyl acrylates,C₁-C₂₀ alkyl methacrylates, C₂-C₂₀ alkenyl acrylates, C₂-C₂₀ alkenylmethacrylates, C₅-C₈ cycloalkyl acrylates, C₅-C₈ cycloalkylmethacrylates, phenyl acrylates, phenyl methacrylates,phenyl(C₁-C₉)alkyl acrylates, phenyl(C₁-C₉)alkyl methacrylates,substituted phenyl (C₁-C₉)alkyl acrylates, substitutedphenyl(C₁-C₉)alkyl methacrylates, phenoxy(C₁-C₉)alkyl acrylates,phenoxy(C₁-C₉)alkyl methacrylates, substituted phenoxy(C₁-C₉)alkylacrylates, substituted phenoxy(C₁-C₉)alkyl methacrylates, C₁-C₄alkoxy(C₂-C₄)alkyl acrylates, C₁-C₄ alkoxy (C₂-C₄)alkyl methacrylates,C₁-C₄ alkoxy(C₁-C₄)alkoxy(C₂-C4)alkyl acrylates, C₁-C₄alkoxy(C₁-C₄)alkoxy(C₂-C₄)alkyl methacrylates, C₂-C₄ oxiranyl acrylates,C₂-C₄ oxiranyl methacrylates, copolymerizable di-, tri-or tetra-acrylatemonomers, copolymerizable di-, tri-, or tetra-methacrylate monomers. Thefirst composition may include up to about 5% by weight of anethylenically substituted monomer.

Examples of such monomers include methyl methacrylate, ethylmethacrylate, propyl methacrylate, isopropyl methacrylate, butylmethacrylate, isobutyl methacrylate, hexyl methacrylate, 2-ethylhexylmethacrylate, nonyl methacrylate, lauryl methacrylate, stearylmethacrylate, isodecyl methacrylate, ethyl acrylate, methyl acrylate,propyl acrylate, isopropyl acrylate, butyl acrylate, isobutyl acrylate,hexyl acrylate, 2-ethylhexyl acrylate, nonyl acrylate, lauryl acrylate,stearyl acrylate, isodecyl acrylate, ethylene methacrylate, propylenemethacrylate, isopropylene methacrylate, butane methacrylate,isobutylene methacrylate, hexene methacrylate, 2-ethylhexenemethacrylate, nonene methacrylate, isodecene methacrylate, ethyleneacrylate, propylene acrylate, isopropylene, hexene acrylate,2-ethylhexene acrylate, nonene acrylate, isodecene acrylate, cyclopentylmethacrylate, 4-methyl cyclohexyl acrylate, benzyl methacrylate,o-bromobenzyl methacrylate, phenyl methacrylate, nonylphenylmethacrylate, benzyl acrylate, o-bromobenzyl phenyl acrylate,nonylphenyl acrylate, phenethyl methacrylate, phenoxy methacrylate,phenylpropyl methacrylate, nonylphenylethyl methacrylate, phenethylacrylate, phenoxy acrylate, phenylpropyl acrylate, nonylphenylethylacrylate, 2-ethoxyethoxymethyl acrylate, ethoxyethoxyethyl methacrylate,2-ethoxyethoxymethyl acrylate, ethoxyethoxyethyl acrylate, glycidylmethacrylate, glycidyl acrylate, 2,3-epoxybutyl methacrylate,2,3-epoxybutyl acrylate, 3,4-epoxybutyl acrylate, 3,4-epoxybutylmethacrylate, 2,3-epoxypropyl methacrylate, 2,3-epoxypropyl acrylate2-methoxyethyl methacrylate, 2-ethoxyethyl methacrylate, 2-butoxyethylmethacrylate, 2-methoxyethyl acrylate, 2-ethoxyethyl acrylate,2-butoxyethyl acrylate, tetrahydrofurfuryl acrylate, tetrahydrofurfurylmethacrylate, ethoxylated bisphenol-A-dimethacrylate, ethylene glycoldiacrylate, 1,2-propane diol diacrylate, 1,3-propane diol diacrylate,1,2-propane diol dimethacrylate, 1,3-propane diol dimethacrylate,1,4-butane diol diacrylate, 1,3-butane diol dimethacrylate, 1,4-butanediol dimethacrylate, 1,5 pentane diol diacrylate,2,5-dimethyl-1,6-hexane diol dimethacrylate, diethylene glycoldiacrylate, diethylene glycol dimethacrylate, trimethylolpropanetrimethacrylate, tetraethylene glycol diacrylate, tetraethylene glycoldimethacrylate, dipropylene glycol dimethacrylate, trimethylolpropanetriacrylate, glycerol triacrylate, glycerol trimethacrylate,pentaerythritol triacrylate, pentaerythritol dimethacrylate,pentaerythritol tetracrylate, pentaerythritol tetramethacrylate.

The first composition may also include amines. Examples of aminessuitable for incorporation into an antireflective coating compositioninclude tertiary amines and acrylated amines. The presence of an aminetends to stabilize the antireflective coating composition. Theantireflective coating composition may be prepared and stored prior tousing. In some embodiments, the antireflective coating composition mayslowly gel due to the interaction of the various components in thecomposition. The addition of amines tends to slow down the rate ofgelation without significantly affecting the antireflective propertiesof subsequently formed coatings. The first composition may include up toabout 5% by weight of amines.

The first composition may also include colloidal silica. Colloidalsilica is a suspension of silica particles in a solvent. The silicaparticles may have a particle size of about 1 nanometer to about 100nanometers in diameter. Amorphous silica particles may be dispersed inwater, a polar solvent, or combinations of water and a polar solvent.Some polar solvents that may be used include, but are not limited tomethanol, ethanol, isopropanol, butanol, ethylene glycol, and mixturesof these solvents. One example of colloidal silica is commerciallyavailable from Nissan Chemical Houston Corp., Houston, Tex., and soldunder the trade name Snowtex. The first composition may include up toabout 5% by weight of colloidal silica.

The first composition may also include a photoinitiator and/or aco-initiator. Examples of photoinitiators and co-initiators have beenpreviously described. Up to about 1% by weight of the first coatingcomposition may include a photoinitiator or a combination of aphotoinitiator and a co-initiator.

The first composition may also include a fluorinated ethylenicallysubstituted monomer. Fluorinated ethylenically substituted monomers havethe general structure:

CH₂═CR¹CO—O—(CH₂)_(p)—C_(n)F_(2n+1)

Where R¹ is H or —CH₃; p is 1 or 2; and n is an integer from 1 to 40.Examples of fluorinated ethylenically substituted monomer include, butare not limited to, trihydroperfluoroheptyl acrylate andtrihydroperfluoroheptyl acrylate. The addition of a fluorinatedethylenically substituted monomer to a composition to be applied to aplastic lens may increase the hydrophobicity of the coating.Hydrophobicity refers to the ability of a substrate to repel water. Theaddition of a fluorinated ethylenically substituted monomer to thecomposition may increase the ability of the coated substrate to resistdegradation due to exposure to water.

The first composition may be applied to one or both surfaces of aplastic lens. The antireflective coating composition may be appliedusing a coating unit such as the one described previously. Theantireflective coating composition may be applied to the eyeglass lensas the lens is rotated within the coating unit. The plastic lens may berotated at speeds up to about 2000 rpm as the first composition is addedto the plastic lens. Less than 1 mL of the antireflective coatingcomposition may be applied to the eyeglass lens. More than 1 ml may alsobe applied, however, this amount may be excessive and much of theantireflective coating composition may be flung from the surface of thelens.

The thickness of the applied antireflective coating composition may alsodepend on the speed of rotation of the eyeglass lens, the viscosity ofthe antireflective coating composition, the amount of composition addedto the eyeglass lens, and the volatility of the solvent used to dissolvethe components of the composition. As an antireflective coatingcomposition is added to a rotating eyeglass lens, the antireflectivecoating is spread evenly across the surface of the eyeglass lens. Thesolvent used to dissolve the components of the antireflective coatingcomposition may evaporate as the composition is applied to the eyeglasslens surface, leaving a thin film of the antireflective coatingcomponents. As additional antireflective coating material is added, thethickness of the antireflective coating layer will gradually beincreased. The rate at which the thickness increases is related to thespeed of rotation of the eyeglass lens, the viscosity of theantireflective coating composition, and the volatility of the solventused to form the composition.

When the composition is applied to a surface of the lens by a humanoperator, the thickness of the first coating composition may vary due tothe operators inability to consistently add the composition to the lensat the same rate each time. To overcome this variability, thecomposition may be added to the plastic lens with an automateddispensing system. The automated dispensing system may include a syringefor holding the composition and a controller drive system forautomatically moving the plunger of the syringe. Such systems arecommercially available as syringe pumps. A syringe pump may be coupledto a syringe that includes the composition to be added to the lens. Thesyringe pump may be configured to dispense the composition at apreselected rate. In this manner the rate at which the composition isadded to the surface may be accurately controlled. In anotherembodiment, the dispenser system may include a conveyor for drawing thesyringe and syringe pump across the surface of the lens. As thecomposition is dispensed by the syringe, the conveyor system may drawthe syringe across the surface of the lens. In this manner the rate ofapplication and the distribution path of the composition may beperformed in a consistent manner

Assuming a constant speed of rotation of the eyeglass and a constantdispensing rate, as the viscosity of the antireflective coatingcomposition is increased, the rate at which the thickness of the appliedantireflective coating composition increases may increase.Alternatively, the rate at which the thickness of the antireflectivecoating composition increases may be altered by adjusting the rotationspeed of the eyeglass lens. Assuming a constant viscosity of theantireflective coating composition, as the rotational speed of theeyeglass lens is increased, less of the antireflective coatingcomposition will remain on the eyeglass lens as the composition isapplied. By slowing down the rotational speed of the eyeglass lens, thethickness of the antireflective coating layer may be increased.

Alternatively, the viscosity of the first composition may be changed byaltering the amount of metal alkoxide and other components present inthe first composition. For example, a first composition that includes ametal alkoxide at a concentration of about 5% by weight, will have agreater viscosity than a composition that has a metal alkoxideconcentration of about 2.5%. The more viscous composition will leave athicker film on the surface of the lens than the less viscouscomposition. When the composition is cured a thicker first coating layermay be obtained. The viscosity may also be altered by changing theorganic solvent that the metal alkoxide is dissolved or suspended in.Each solvent may have an inherent viscosity that may effect the overallviscosity of the first composition. By changing the solvent thisinherent viscosity may be altered, thus altering the viscosity of theoverall composition.

As an antireflective coating composition is added to a rotating eyeglasslens, the antireflective coating is spread evenly across the surface ofthe eyeglass lens. If a solvent used to dissolve the components of theantireflective coating composition has a relatively low boiling point(e.g., below about 80° C.) the solvent will evaporate and allow the moreviscous components of the antireflective coating composition (e.g., thesilane, organic monomers, metal alkoxide, etc.) to form a coating on thelens. As more composition is added to the eyeglass lens, the thicknessof the antireflective coating may increase. By changing solvent used inthe antireflective coating composition to a more volatile solvent, therate at which the thickness of the antireflective coating grows mayincrease. Generally, a low boiling point solvent will give a thickercoating layer than a higher boiling point solvent.

In general, the ability to control the thickness of the applied firstcomposition may be important for achieving antireflective properties. Insome embodiments, a low viscosity and/or low concentration compositionmay be used to form the first coating layer. Such compositions may formrelatively thin films on the surface of the plastic lens. In someembodiments, the thickness of the formed film may be too thin for thedesired application. In an alternate procedure, the first coating layermay be formed by repeatedly applying the first composition to theplastic lens and curing the deposited composition. Each iteration ofthis process will create a thicker first coating layer. When the firstcoating layer reaches a preselected thickness the procedure may bestopped and the second coating layer may be formed.

After applying the first composition to the plastic lens, the firstcomposition may be cured to form the first coating layer. Curing of thefirst composition may be accomplished by a variety of methods. In oneembodiment, the first composition may cured by spinning the lens untilthe composition forms a gel. Alternatively, the composition may beallowed to sit at room temperature for a time sufficient to allow thecomposition to gel. The gelled composition has a higher index ofrefraction than the underlying plastic lens, and may therefore serve asthe first coating layer. Additionally, at least a portion of the gelledcomposition may be sufficiently adhered to the plastic lens such that aportion of the gelled composition may remain on the lens during theapplication of the second composition, thus providing antireflectiveproperties to the lens subsequent to formation of the second coatinglayer.

Alternatively, the first composition may be cured by the application ofheat to the composition. After the first composition is deposited on thelens and spin dried, the first composition may be in a gelled state. Thegelled composition may be heated for a period of about 1-10 minutes at atemperature in the range from about 40° C. to about 120° C., preferablyabout 100° C. Heating of the gelled composition in this matter may causethe composition to be converted from a gelled state to a hardened state.The heat cured first coating layer may exhibit good adhesion to theunderlying lens. In some cases, however, the flow characteristics of thesecond composition when applied to a heat cured first composition mayexhibit a non-uniform distribution across the surface of the cured firstcomposition. Furthermore, the first coating layer may have an index ofrefraction that is greater than the index of refraction of the plasticlens.

In another embodiment, the first composition may be cured by theapplication of ultraviolet light. As described above, the firstcomposition is applied to the lens and dried to form a gelledcomposition. The gelled composition may be treated with ultravioletlight for a time sufficient to convert the gelled composition to ahardened state. In some embodiments, the gelled composition is treatedwith ultraviolet light for a time of about 60 seconds or less. In oneembodiment, the ultraviolet light source may be a germicidal lamp, asdescribed above in the spin coating unit (See FIGS. 2 and 3). It shouldbe noted that germicidal lamps produce no significant heat energy. Thus,it is believed that the accelerated curing of the first composition isdue to the presence of the ultraviolet light, rather than from any heatproduced by the lamps. Advantageously, it has been found that the use ofultraviolet light to cure the first composition may provide a surfacethat allows a uniform distribution of a subsequently appliedcomposition. In comparison, the use of heating to cure the firstcomposition may provide a surface that causes a subsequently appliedcomposition to be unevenly dispersed. Thus the use of ultraviolet lightmay offer an advantage over heat curing with regard to formingmultilayer antireflective coatings.

It is believed that the ultraviolet light accelerates the condensationreaction of the metal alkoxide. The ultraviolet light may interact withthe metal alkoxide and excite the electrons of the metal alkoxide, whichin turn may accelerate the polymerization of the metal alkoxide. It isbelieved that most metal alkoxides have a strong absorbance in theultraviolet region, specifically at wavelengths below about 300 nm. Forexample, titanium isopropoxide has a maximum absorbance at 254 nm. Insome embodiments, the application of ultraviolet light to the metalalkoxide may be directed toward the coated surface rather than throughthe substrate. Many visible light transmitting media e.g., borosilicateglasses and plastics, may not allow sufficient amounts of light to passthrough to the coating composition at the appropriate wavelength.

After the first coating layer has been applied and cured, a secondcoating layer may be formed upon the first coating layer. The secondcoating layer may be formed by applying a second composition to theexposed surface of the first coating layer. In some embodiments, thesecond coating layer, after curing, is composed of a material that hasan index of refraction that is substantially less than the first coatinglayer.

The second composition, in an embodiment, may be composed of aninitiator and an ethylenically substituted monomer. The ethylenicallysubstituted monomers that may be used have been described previously.The initiator may be a photoinitiator, such as was described earlier.Alternatively, the initiator may be a metal alkoxide. It is believedthat both photoinitiators and metal alkoxides interact with ultravioletlight and this interaction causes the initiation of polymerization ofthe ethylenically substituted monomer. The second composition may beapplied to the first coating layer in a manner similar to thosedescribed earlier. The second composition may include other monomerssuch as silane monomers, colloidal silica, coinitiators, and fluorinatedethylenically substituted monomer.

The combination of a second low index of refraction coating layer formedupon a first high index of refraction coating material may provideimproved light transmission through the underlying substrate. The use ofmetal alkoxides in one or both layers tends to improve the adhesion ofthe coating material to the underlying substrate.

Antireflective coatings are thin films that are formed upon the surfaceof the eyeglass lens. Such films have an optical thickness that isherein defined as the index of refraction of the film times themechanical thickness of the film. The most effective films typicallyhave an optical thickness that is a fraction of a wavelength of incidentlight. Typically the optical thickness is one-quarter to one-half thewavelength. Thus for visible light (having a wavelengths approximatelybetween 400 nm and 700 nm) an ideal antireflective coating layer shouldhave a thickness between about 100 and 200 nm. Thicknesses that are lessthan 100 nm or greater than 200 nm may also be used, although suchthickness may not provide an optimal transmittance. In the embodimentscited herein, the combined optical thickness of the coating material maybe up to about 1000 nm, more particularly up to about 500 nm.

The ideal thickness of an antireflective coating should be aboutone-quarter the wavelength of the incident light. For light entering thefilm at normal incidence, the wave reflected from the second surface ofthe film will be exactly one-half wavelength out of phase with the lightreflected from the first surface, resulting in destructive interference.If the amount of light reflected from each surface is the same, acomplete cancellation will occur and no light will be reflected. This isthe basis of the “quarter-wave” low-reflectance coatings which are usedto increase transmission of optical components. Such coatings also tendto eliminate ghost images as well as the stray reflected light.

Because visible light includes a range of wavelengths from about 400 nmto about 700 nm, a quarter-wave coating will only be optimized for onewavelength of light. For the other wavelengths of light theantireflective coating may be either too thick or too thin. Thus, moreof the light having these wavelengths may be reflected. For example, anantireflective coating that is designed for interior lights (e.g.,yellow light) will have a minimum reflectance for yellow light, whilethe reflectance for blue or red light will be significantly higher. Thisis believed to be the cause of the characteristic purple color of singlelayer low-reflectance coatings for many camera and video lenses. In oneembodiment, the thickness of the antireflective coating layers of aneyeglass lens may be varied or the indices of refraction may be alteredto produce lenses which have different visible light reflectivecharacteristics. Both of these variations will alter the opticalthickness of the coating layers and change the optimal effectivewavelength of light that is transmitted. As the optical thickness of thecoating layers is altered the reflected color of the lens will also bealtered. In an iterative manner, the optimal reflected color of theeyeglass lens may be controlled by the manufacturer.

While two layer antireflective coatings have been described, it shouldbe understood that multi-layer systems that include more than two layersmay also be used. In a two-layer system, a substrate is coated with ahigh index of refraction layer. The high index of refraction layer isthen coated with a low index of refraction layer. In an embodiment, athird high index of refraction (e.g., at least higher than theunderlying second coating layer) may be formed on the second coatinglayer. A fourth low index of refraction layer (e.g., at least lower thanthe index of refraction of the third coating layer) may also be formed.The four layer stack may exhibit antireflective properties. The fourlayer stack may have an optical thickness of less than about 1000 nm,and more particularly less than about 500 nm. Additional layers may beformed upon the stack in a similar manner with the layers alternatingbetween high and low index of refraction materials.

In another embodiment, the second coating layer may be formed as acombination of two chemically distinct compositions. The second coatinglayer may be formed by forming a silicon layer upon the first coatinglayer. The silicon layer may be formed from colloidal silica or a silanemonomer. The silicon layer is applied to the first coating layer and atleast partially cured. The silicon layer may be cured by drying,heating, or the application of ultraviolet light.

To complete formation of the second coating layer, a second compositionis deposited onto the silicon layer. The second composition may includean ethylenically substituted monomer and an initiator. The ethylenicallysubstituted monomers that may be used have been described previously.The initiator may be a photoinitiator, such as was described earlier.Alternatively, the initiator may be a metal alkoxide. The secondcomposition may be applied to the silicon layer in a manner similar tothose described earlier. The second composition may include othermonomers such as silane monomers, colloidal silica, coinitiators, andfluorinated ethylenically substituted monomers. The second compositionmay be cured by the application of ultraviolet light.

The silicon layer, when partially cured or fully cured, tends to exhibita porous structure. It is believed that the addition of the secondcomposition to a substantially porous silicon layer may allow betterchemical interaction between the second composition and the siliconlayer. In general, good antireflective properties are seen when asilicon layer is placed upon a first coating layer, when the firstcoating layer includes a metal alkoxide. The silicon layer, however, mayexhibit poor adhesion to a metal alkoxide containing underlying layer.The adhesion of the silicon layer may be improved by the addition of ametal alkoxide to the composition used to form the silicon layer.Silicon containing compositions, such as compositions that includecolloidal silica or silane monomers, tend to be unstable in the presenceof a metal alkoxide. Generally, it was observed that the mixture ofsilicon containing compounds with metal alkoxides produces a cloudycomposition, and in some cases gelation, prior to the application of thecomposition to the first coating layer. Such gelation tends to increasethe haze observed in the coated lens. The reactivity of metal alkoxideswith silicon containing compositions tends to reduce the shelf life ofsuch compositions, making it difficult to store the composition forextended periods of time.

By separating the metal alkoxide from the silicon containingcompositions and applying the compositions in a sequential manner, manyof the above-described problems may be reduced. It is believed that theaddition of a metal alkoxide containing composition to an at leastpartially cured silicon layer, causes the second composition to interactwith the underlying silicon composition such that a composite layer isformed. This composite layer may exhibit properties that are similar tothe properties found for single layers formed from compositions thatinclude silicon compounds and metal alkoxides. Since the siliconcontaining composition and metal alkoxide containing compounds areapplied at different times, the compositions may be stored separately,effectively overcoming the shelf life problems.

In one embodiment, a hardcoat composition may be applied to the plasticlens prior to the application of the antireflective coating stack.Curing of the hardcoat composition may create a protective layer on theouter surface of the plastic lens. Typically, hardcoat compositions areformed from acrylate polymers that, when cured, may be resistant toabrasive forces and also may provide additional adhesion for theantireflective coating material to the plastic lens.

In another embodiment, a hydrophobic coating may be placed onto theantireflective coating. Hydrophobic coatings may include fluorinatedethylenically substituted monomers. Curing of the hydrophobic coatingmay create a water protective layer on the outer surface of theantireflective coating. The hydrophobic layer may help preventdegradation of the lens due to the interaction of atmospheric water withthe lens.

In the above described procedures, the antireflective coating may beformed onto a preformed lens. Such a method may be referred to as anout-of-mold process. An alternative to this out-of-mold process is anin-mold process for forming antireflective coatings. The “in-mold”process involves forming an antireflective coating over an eyeglass lensby placing a liquid lens forming composition in a coated mold andsubsequently curing the lens forming composition. The in-mold method isadvantageous to “out-of-mold” methods since the in-mold method exhibitsless occurrences of coating defects manifested as irregularities on theanterior surface of the coating. Using the in-mold method produces anantireflective coating that replicates the topography and smoothness ofthe mold casting face.

The application of an antireflective coating to a plastic lens requiresthat the first and second coating layers (or more if a multi layer stackis used) be formed onto the mold. In particular, the second coatinglayer is placed onto the mold prior to forming the first coating layer.In this manner the stack is built backwards. The top of the stack on thecasting surface of the mold may be the first coating layer which is tocontact the underlying lens in the in-mold process.

In an embodiment, a second coating layer may be formed by applying asecond composition upon a casting surface of a mold and curing thesecond composition. The second composition, in an embodiment, includes aphotoinitiator and an ethylenically substituted monomer. Theethylenically substituted monomers that may be used have been describedpreviously. The initiator may be a photoinitiator, such as was describedearlier. The second composition may include other additives such ascoinitiators and fluorinated ethylenically substituted monomer. Thesecond composition may, in some embodiments, be substantially free ofmetal alkoxides. It is believed that metal alkoxides disposed within acomposition may interact with the glass and inhibit the removal of thelens from the molds. The second monomers and other additives of thesecond composition may be dissolved or suspended in an organic solvent.The organic solvent may be used to aid in the application of the monomerto the mold surface.

To apply the second composition to the mold member, the mold member maybe spun so that the second composition becomes distributed over thecasting face. The mold member is preferably rotated about asubstantially vertical axis at a speed up to about 2000 revolutions perminute, preferably at about 850 revolutions per minute. Further, adispensing device may be used to direct the composition onto the castingface while the mold member is spinning. The dispensing device may movefrom the center of the mold member to an edge of the mold member.

After applying the second composition to the mold member, ultravioletlight may be directed at the mold member to cure at least a portion ofthe second composition. The ultraviolet light may be directed towardeither surface (i.e., the casting or non-casting faces) of the mold tocure the second composition.

After the second composition is at least partially cured, a firstcoating layer may be formed on the second composition by applying afirst composition to the second composition. The first composition mayinclude a metal alkoxide. The first composition may also include otheradditives such as photoinitiators, coinitiators, silane monomers,colloidal silica, ethylenically substituted monomers, and fluorinatedethylenically substituted monomers. The metal alkoxide and otheradditives may be dissolved in an organic solvent. All of these compoundshave been described previously.

The first composition may be cured by a variety of methods. In oneembodiment, the first composition may be cured by spinning the lensuntil the composition forms a gel. Alternatively, the composition may beallowed to sit at room temperature for a time sufficient to allow thecomposition to gel. In another embodiment, the first composition may becured by the application of heat to the composition. After the firstcomposition is deposited on the lens and spin dried, the firstcomposition may be in a gelled state. The gelled composition may beheated for a period of about 1-10 minutes at a temperature in the rangefrom about 40° C. to about 120° C. Heating of the gelled composition inthis matter may cause the composition to be converted from a gelledstate to a hardened state. In another embodiment, the first compositionmay be cured by the application of ultraviolet light. As describedabove, the first composition is applied to the lens and dried to form agelled composition. The gelled composition may be treated withultraviolet light for a time sufficient to convert the gelledcomposition to a hardened state. In some embodiments, the gelledcomposition is treated with ultraviolet light for a time of about 60seconds or less. In one embodiment, the ultraviolet light source may bea germicidal lamp.

After the formation of the first and second coating layers on thecasting surface of the mold member, the mold member may be assembledwith a second mold member by positioning a gasket between the members toseal them. The second mold member may also include an antireflectivecoating on the second molds casting surface. The antireflective coatingon the second mold may have an identical composition as theantireflective coating on the first mold. Alternatively, theantireflective coatings may have different compositions. The combinationof the two molds and gasket form a mold assembly having a cavity definedby the two mold members. The casting surfaces, and therefore theantireflective coatings, may be disposed on the surface of the formedmold cavity.

After the mold assembly has been constructed, a lens forming compositionmay be disposed within the mold assembly. An edge of the gasket may bedisplaced to insert the lens forming composition into the mold cavity.Alternatively, the gasket may include a fill port that will allow theintroduction of the lens forming composition without having to displacethe gasket. This lens forming composition includes a photoinitiator anda monomer that may be cured using ultraviolet light. Examples of lensforming compositions that may be used include, but are not limited to,OMB-99 and PhasesII monomers, as described above. When disposed withinthe mold cavity, the lens forming composition, in some embodiments, isin contact with the antireflective coating formed on the castingsurfaces of the molds.

In some embodiments, an adhesion coating layer may be formed on thepartially cured first composition. The coating adhesion layer may beformed from an adhesion composition that is applied to the first coatinglayer and cured. The adhesion composition may include an ethylenicallysubstituted monomer and a photoinitiator. It is believed that curing ofthe first composition may reduce the adhesion of the first coating layerto a subsequently formed plastic lens. The adhesion coating layer maytherefore improve the adhesion between the first coating composition andthe subsequently formed lens. The adhesion layer composition, in someembodiments, includes monomers similar to the monomers included in thelens forming composition. This may improve the adhesion between theadhesion layer and a lens formed from the lens forming composition. Theadhesion layer may have an index of refraction that is similar, or lessthan, the index of refraction of the formed lens. Thus, the adhesionlayer may have little, if any, affect on the antireflective propertiesof the first and second coating layers.

While two layer antireflective coatings have been described for anin-mold process, it should be understood that multi-layer systems thatinclude more than two layers may also be used. In a two layer system, amold is coated with a low index of refraction layer. The low index ofrefraction layer is then coated with a high index of refraction layer.In an embodiment, a third low index of refraction layer (e.g., at leastlower than the underlying first coating layer) may be formed on thefirst coating layer. A fourth high index of refraction layer (e.g., atleast higher than the index of refraction of the third coating layer)may also be formed. The four layer stack may exhibit antireflectiveproperties. The four layer stack may have an optical thickness of lessthan about 1000 nm, and more particularly less than about 500 nm.Additional layers may be formed upon the stack in a similar manner withthe layers alternating between high and low index of refractionmaterials.

In another embodiment, the second coating layer may be formed as acombination of two chemically distinct compositions. The second coatinglayer may be formed by forming an organic containing layer upon thecasting surface of the mold. The organic containing layer includes anethylenically substituted monomer and an initiator. The ethylenicallysubstituted monomers that may be used have been described previously.The initiator may be a photoinitiator, such as was described earlier.Alternatively, the initiator may be a metal alkoxide. The organiccontaining layer may be applied to the casting surface in a mannersimilar to those described earlier. The organic containing layer mayinclude other monomers such as silane monomers, colloidal silica,coinitiators, and fluorinated ethylenically substituted monomers. Theorganic containing layer may be cured by the application of ultravioletlight.

The second coating layer may be completed by applying a silicon layerupon the organic containing layer. The silicon layer may be formed fromcolloidal silica or a silane monomer. The silicon layer is applied tothe organic containing layer and at least partially cured. The siliconlayer may be cured by drying, heating, or the application of ultravioletlight.

Additional coating materials may be placed onto the antireflectivecoating. In one embodiment, a hardcoat composition may be applied to theantireflective coating formed on the casting surface of a mold. Curingof the hardcoat composition may create a protective layer on the outersurface of a subsequently formed plastic eyeglass lens. Typicallyhardcoat compositions are formed from acrylate polymers that, whencured, are resistant to abrasive forces. The subsequently formedhardcoat layer may help to prevent abrasions to the plastic lens. Othercoatings that may be formed include hydrophobic coatings and tintedcoatings. Such coatings may be formed on the casting surface of themold, prior to the formation of the antireflective coatings. Thesecoatings, in some embodiments, may allow the formed lens to be removedmore easily from the mold assembly. As discussed above, theantireflective coatings may adhere to the molds, making removal of thelens form the mold assembly difficult. The use of hydrophobic coatingsmay reduce the adhesion between the mold assemblies and theantireflective coating layer.

EXAMPLES

A plastic eyeglass lens was made according to the process describedabove from the OMB-99 monomer solution. The lens was then coated withtwo antireflective coating compositions. In all of the examples, thefollowing abbreviations are used:

“AC” is acetone, commercially available from Aldrich;

“AA” is an acrylic amine commercially available as CN384 from Sartomer;

“Al” is aluminum tri-sec-butoxide (98%) commercially available fromAvocado;

“AS” is 3-aminopropyltrimethoxysilane (97%) commercially available fromAldrich; “BDK”, “BDM”, and “BDMK” are Photomer 51 and2,2-dimethoxy-2-phenylacetophenone commercially available from Henkel;

“BYK300” is a solution of polyether modified dimethylpolysiloxanecopolymer commercially available from BYK Chemie;

“CD1012” is diaryl iodonium hexafluoroantimonate commercially availablefrom Sartomer;

“CD540” is ethoxylated bisphenol A dimethacrylate commercially availablefrom Sartomer;

“CN124” is epoxy acrylate commercially available from Sartomer;

“Cynox1790” istris(4-t-butyl-3-hydroxy-2,6-dimethylbenzyl)-s-triazine-2,4,6-(1H, 3H,5H)-trione commercially available from Sartomer;

“D1173” is 2-hydroxy-2-methyl-1-phenyl-propan-1-one (HMPP) commerciallyavailable from Ciba;

“DC193” is a surfactant commercially available from Dow Corning;

“ECHMCHC” is 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexane carboxylate;

“Eosin” is the dye Eosin Y commercially available from Aldrich;

“EtOH” is ethanol, commercially available from Fisher;

“FC40” and “FC430” are surfactants commercially available from 3M;

“FC-171” is a fluorochemical surfactant commercially available from 3M;

“FC-725” also known as FLUORAD, a fluorochemical surfactant commerciallyavailable from 3M;

“GPTMS” is 3-glycidoxypropyltrimethoxysilane commercially available fromAldrich;

“HC-8” is a hard coat forming composition commercially available fromFastcast Co. and includes a mixture of SR399, SR601, Irg184, and MP;

“HC8558” is commercially available from GE;

“HC-900” is commercially available from Coburn Optical Industries;

“HEMA” is hydroxyethyl methacrylate commercially available from CoburnOptical Industries;

“HR-200” is a hydrophobic coating commercially available from GroupCouget;

“IPA” is isopropyl alcohol commercially available from Fisher;

“Irg 184” is Irgacure 184 or 1-Hydroxycyclohexyl phenyl ketonecommercially available from Ciba;

“Irg 261” is Irgacure 261 or iron (.eta.5-2,4-cyclopentadien-1-yl)[1,2,3,4,5,6-.eta.)-(1-methylethyl)benzene]-hexafluorophosphate)commercially available from Ciba;

“Irg 819” is Irgacure 819 or Phosphine oxide, phenylbis(2,4,6-trimethylbenzoyl) commercially available from Ciba;

“MP” is 1-methoxy-2-propanol commercially available from Arcos;

“Nalco Si2326” is a colloidal silica commercially available from NalcoChemical Company;

“NNDMEA” is N,N-dimethylethanolamine commercially available fromAldrich;

“PerenolS-5” is a modified polysiloxane commercially available fromHenkel;

“PFOA” is 1H, 1H-perfluorooctyl acrylate commercially available fromLancaster;

“PFOFCS” is 1H,1H,2H.2H-perfluorooctyltrichlorosilane commerciallyavailable from Lancaster;

“PFOMA” is perfluorooctyl methacrylate commercially available fromLancaster;

“Q4DC” is an organic functional silicone fluid commercially availablefrom Dow Corning;

“Si” is MA-ST-S (30% colloidal silica in 70% methanol) commerciallyavailable from Nissan Chemical;

“SR123” is an acrylate monomer commercially available from Sartomer;

“SR306” is tripropylene glycol diacrylate commercially available fromSartomer;

“SR313” is lauryl methacrylate commercially available from Sartomer;

“SR368” is tris(2-hydroxy ethyl) isocyanurate triacrylate commerciallyavailable from Sartomer;

“SR399” is dipentacrythritol tetraacrylate commercially available fromSartomer;

“SR423” is isobornyl methacrylate commercially available from Sartomer;

“SR444” is Pentaerythritol triacrylate commercially available fromSartomer;

“SR640” is tetrabromo bisphenol A diacrylate commercially available fromSartomer;

“SR9003” is propoxylated neopentyl glycol diacrylate commerciallyavailable from Sartomer;

“T770” is bis(2,2,6,6-tetramethyl-4-piperidinyl sebacate commerciallyavailable from Ciba;

“TEA” is triethylamine commercially available from Aldrich;

“TFEMA” is trifluoroethyl methacrylate commercially available fromCornelius Chemical;

“Ti” is titanium (IV) isoproxide commercially available from Aldrich;

“Ti-Bu” is titanium (IV) butoxide commercially available from Aldrich;

“TMSPMA” is 3-(trimethoxysilyl)propyl methacrylate commerciallyavailable from Aldrich;

“TPB” is thermoplast blue 684;

“TPR” is thermoplast red 454;

“TX-100” is a surfactant commercially available from Aldrich;

“ZelecUN” is a lubricant commercially available from Stepan; and

“Zr” is zirconium (IV) propoxide commercially available from Aldrich.

In Table 1, Layer 1 refers to the first antireflective coating layer,Layer 2 refers to the second antireflective coating layer. Solutions ofeach of the components were prepared and used to form the antireflectivecoatings. For all of the compositions listed in Table 1, the remainderof the composition is made up of 1-methoxy-2-propanol. For example, alisting of 5% Ti, should be understood to mean 5% by weight of Ti and95% by weight of 1-methoxy-2-propanol.

The plastic eyeglass lens was coated using two different coatingcompositions. The “Layer 1” composition was added to a surface of theeyeglass lens and the eyeglass lens was rotated on a lens spin-coatingapparatus. After the L1 composition was spread onto the eyeglass lenssurface the solvent was allowed to substantially evaporate and theremaining composition was subjected to ultraviolet light from thegermicidal lamp from the previously described coating unit for about 60seconds. In some instances, more or less UV light was applied. Alternatetimes are noted in parenthesis. The “Layer 2” composition was added tothe eyeglass lens after the Layer 1 composition was cured. The eyeglasslens was spun on a lens spin-coating apparatus until the solvent wassubstantially evaporated. Layer 2 was then cured by the application ofultraviolet light from the germicidal lamp from the previously describedcoating unit. Curing time of the second layer is 60 seconds, unlessotherwise noted. The % transmittance refers to the amount of lighttransmitted through the lens after the Layer 2 composition was cured.The transmittance was measured in a BYK Gardner Haze Guard Plus Meter,available from BYK Gardner, Silver Springs, Md. Transmission readingswere taken of an uncoated lens to use as a control standard. The visiblelight transmittance of an uncoated lens measured with the convex face ofthe lens positioned against the haze port of the BYK Gardner Haze GuardPlus Meter is about 92%. Color refers to the color of the lightreflected from the coated lens.

TABLE 1 Visible Light Ex. # Layer 1 Layer 2 Transmittance % Color  1 5%Ti 5.1% Si 99.0% RED 1.04% Ti 1.04% GPTMS 0.144% HC-900 (Heat 20 Min.) 2 5% Ti 4.25% Si 99.0% 0.87% GPTMS 0.1 7HC-900 (Heat 20 Min.)  3 5% Ti4.5% Si 96.0% PURPLE 1.8% Ti 1.8% GPTMS 0.17% HC-900 (Heat 20 Min.)  45% Ti 4.25% Si 99.0% 1.04% Ti 0.87% GPTMS 0.17% HC-900 (Heat 20 Min.)  55% Ti 4.5% Si 97.4% BLUE 1.8% Ti 1.8% GPTMS 0.17% HC-900  6 3% Ti 4.5%Si 97.0% PURPLE 1.8% Ti 1.8% GPTMS 0.17% HC-900  7 3% Ti 3% Si 93.0%1.2% Ti 1.2% GPTMS 0.11% HC-900  8 3% Ti 5.4% Si 97.7% RED 1.17% Ti1.17% GPTMS 0.107% HC-900  9 5% Ti 5.4% Si 99.0% PURPLE 1.17% Ti 1.17%GPTMS 0.107% HC-900 10 5.2% Ti 5.4% Si 96.0% 1.33% Si 1.17% Ti 1.33%GPTMS 1.17% GPTMS 0.107% HC-900 11 4.13% Ti 5.4% Si >97%  0.66% Si 1.17%Ti 0.66% GPTMS 1.17% GPTMS 0.107% HC-900 (Heat 5 Min.) 12 5.4% Ti 5.4%Si 98.0% 0.32% Si 1.17% Ti 0.32% GPTMS 1.17% GPTMS 0.053% HC-900 0.107%HC-900 900 (UV 90 s) 13 3% Ti 0.45% Al 97.0% 0.445% Ti 3.5% GPTMS 3.5%TMSPMA 14 3% Ti 03% Al 97.7% 0.36% Ti 2% GPTMS 2% TMSPMA 0.01% TBPO0.05% FC-430 15 3% Ti 0.62% Al >97%  0.17% Ti 1.2% GPTMS 1.2% TMSPMA3.87% HC-8 16 2.8% Ti 0.62% Al >96%  0.49% Al 0.17% Ti 2.79% HC-8 1.2%GPTMS 1.2% TMSPMA 3.87% HC-8 17 3% Ti 0.54% Al 94.4% 0.5% Ti 0.82% GPTMS0.9% TMSPMA 1.27% HC-8 18 3% Ti 0.9% Al 97.3% 0.46% Ti 0.75% GPTMS 0.83%TMSPMA 3.43% HC-8 19 3% Ti 0.8% Al 97.0% 0.1% Ti 0.42% GPTMS 0.42%TMSPMA 6% HC-8 20 3% Ti 0.62% Al 97.0% 0.17% Ti 1.2% GPTMS 1.2% TMSPMA3.9% HC-8 21 10% Ti 0.19% Ti >97%  0.05% Al 0.19% GPTMS 22.7% MP 0.19%TMSPMA 67.25% IPA 1.9% HC-8 3.9% Si 22 10% Ti 0.46% Ti 96.2% 0.05% AA0.9% Al 22.7% MP 0.8% GPTMS 67.25% IPA .75% TMSPMA 3.4% HC-8 23 2% Ti0.3% Al 92.5% 100 ppm AA 18.5% HC-8 25.2% MP (UV 60 s) 72.8% IPA (UV 60s) 24 2% Ti 0.11% Al 92.8% 100 ppm AA 3.35% SR 368 25.2% MP (UV 200 s)72.8% IPA (UV 60 s) 25 1.54% Ti 0.24% Ti 96.3% 77 ppm AA 0.048% Al 42.3%MP 1.94% SR 368 56.2% IPA 1.47% TMSPMA (UV 86 s) 96.3% MP (UV 180 s) 261.54% Ti 0.186% Ti 97.2% 77 ppm AA 0.036% Al 42.3% MP 1.48% SR 368 56.2%IPA 1.13% TMSPMA (UV 40 s) 0.02% DC 193 97.17% MP (UV 180 s) 27 1.54% Ti0.36% Ti 96.8% 77 ppm AA 0.033% Al 42.3% MP 1.39% SR 368 56.2% IPA 1.06%TMSPMA (UV 40 s) 0.0187% DC 193 97.16% MP (UV 10 s) 28 2.8% Ti 2% SR 39996.8% 2.8% Irg 184 (UV 20 s) 29 2.99% Ti 1.86% SR 399 95.7% 0.294% Irg184 0.31% Ti (UV 20 s) (UV 30 s) 30 2.99% Ti 2% SR 399 95.7% GOLD 0.28%Irg 184 0.349% Ti (UV 40 s) (UV 30 s) 31 2.99% Ti 0.34 Ti 95.7% DEEPBLUE 0.28% Irg 184 0.5% SR 306 2% SR 399 (UV 120s) 32 2.99% Ti 2% SR 39995.8% 0.28% Irg 184 0.5% SR 306 (UV 40 s) 0.349% Ti (UV 100 s) 33 2% Ti2% SR 399 95.2% GOLD 0.2 Irg 184 0.4% Ti (UV 30 s) 0.04% Irg 184 (UV 30s) 34 2% Ti 2% SR 399 97.1% 0.2% Irg 184 0.4% Ti (X3) 0.04% Irg 184 (UV20s each) (UV 60 s) 35 2% Ti 2% SR 399 95.6% 0.2 Irg 184 0.4% Ti (UV 30s) 0.04% Irg 184 0.1% BYK 300 (UV 30 s) 36 3.25% Ti 2% SR 399 97.2% GOLD0.1% Irg 184 0.4% Ti (UV 30 s) 0.04% Irg 184 0.1% BYK 300 (UV 30 s) 373.25% Ti 2% SR 399 97.9% 0.1% Irg 184 0.4% Ti (350 rpm) 0.04% Irg 1840.1% BYK 300 (UV 30 s) 38 3.25% Ti 2% SR 399 97.5% GOLD 0.1% Irg 1840.4% Ti (UV 60 s) 0.04% Irg 184 0.1% BYK 300 (UV 60 s) 39 2% Ti 2% SR399 96.0% 0.2% Irg 184 0.4% Ti (UV 60 s) 0.04% Irg 184 0.12% Zelecun (UV60 s) 40 2% Ti 2% SR 399 96.0% 0.2% Irg 184 0.4% Ti (UV 60 s) 0.04% Irg184 0.1% Q4DC 41 3.25% Ti 2% SR 399 97.4% 0.1% Irg 184 0.4% Ti (UV 70 s)0.04% Irg 184 0.1% Q4DC (UV 70 s) 42 3.25% Ti 2% SR 399 97.4% 0.1% Irg819 0.4% Ti (UV 60 s) 0.04% Irg 184 0.1% Q4DC (UV 70 s) 43 3.03% Ti 2%SR 399 96.9% 0.4% Irg 819 0.4% Ti (UV 60 s) 0.04% Irg 184 0.1% Q4DC (UV70 s) 44 2.5% Ti 2% SR 399 96.5% 0.16% Irg 184 0.4% Ti (UV 60 s) 0.04%Irg 184 0.13% FC430 (UV 60 s) 45 3.5% Ti 2% SR 399 97.5% 0.08% Irg 1840.4% Ti (UV 60 s) 0.04% Irg 184 (UV 60 s) 46 3.5% Ti 2% SR 399 98.1%0.08% Irg 184 0.4% Ti (UV 60 s) 0.04% Irg 184 0.1% FC430 0.1% BYK 300(UV 60 s) 47 3.5% Ti 2% SR 399 98.3% 0.08% Irg 184 0.4% Ti (UV 20 s)0.04% Irg 184 0.13% FC430 0.1% BYK 300 (UV 60 s) 48 2.5% Ti 0.2% Ti95.2% 0.2% Irg 184 0.2% SR 239 44.8% AC 0.8% SR 399 52.5% MP 49 2.46% Ti0.5% Ti 97.5% 0.197 Irg 184 0.1% Irg 184 0.157% SR 313 0.55% SR 31344.3% AC 1.75% SR 399 (UV 60 s) 50 3.47% Ti 0.5% Ti 96.9% 0.294% Irg 1840.1% Irg 184 (UV 30 s) 0.55% SR 313 1.75% SR 399 51 2 5% Ti 0.5% Ti97.5% 0.2% Irg 184 0.1% Irg 184 45% AC 0.55% SR 313 52.3% MP 1.75% SR399 (UV 60 s) 52 2.47% Ti 0.53% Ti 97.0% 0.197% Irg 184 0.1% Irg 1840.12% SR 313 0.85% SR 313 44.47% AC 1.38% SR 399 (UV 60 s) (UV 60 s) 532.47% Ti 0.57% Ti 95.0% 0.197% Irg 184 0.087% Irg 184 0.12% SR 313 1.74%CN 124 44.47% AC (UV 60 s) (UV 60 s) 54 2.47% Ti 0.5% Ti 96.8% 0.197%Irg 184 0.19% Irg 184 0.12% SR 313 0.6% CN 124 44.47% AC 0.4% SR 3131.07% SR 399 (UV 60 s) 55 2.47% Ti 0.167% Ti 96.7% 0.197% Irg 184 0.083%Irg 184 0.12% SR 313 0.167% Al 44.47% AC 1.555% SR 399 56 2.47% Ti 0.35%Ti 97.1% 0.197% Irg 184 0.076% Irg 184 0.12% SR 313 0.15% Al 44.47% AC1.43% SR 399 0.414% SR 313 57 5% Ti 2% CD 540 97.6% 0.5% Ti 3.4 ppm TPB0.2 ppm TPR 12 ppm Cynox-1790 58 5% Ti 0.21% Irg 184 97.4% 1.93% CD 5400.48% Ti 3.3 ppm TPB 0.19 ppm TPR 11.6 ppm Cynox-1790 59 5% Ti 0.084%Irg 184 98.5% 0.77% CD 540 0.192% Ti 1.3 ppm TPB 0.075 ppm TPR 4.6 ppm-Cynox-1790 60 5% Ti 2% ECHMCHC 97.6% (UV 60 s) 0.5% Ti 61 5% Ti 0.12%CD 1012 98.1% (UV 40 s) 1.88% ECHMCHC 0.47% Ti (UV 90 s) 62 5% Ti 0.22%CD 1012 95.0% (UV 30 s) 2% ECHMCHC 0.43% Ti (UV 90 s) 63 5% Ti 0.22% CD1012 94.0% (UV 60 s) 2% ECHMCHC 0.43% Ti (UV 90 s) 64 5% Ti 0.356 Ti98.4% 0.073 CD 1012 0.67% ECHMCHC 1.33% SR 399 65 5% Ti 0.14% Irg 18498.3% (UV 50 s) 0.348% Ti 0.07% CD 1012 0.65% ECHMCHC 1.3% SR 399 (Heat)66 5% Ti 0.133% Irg 184 96.4% (UV 45 s) 0.33% Ti 0.066% CD 1012 0.62%ECHMCHC 1.24% SR 399 0.1% Perenol S-5 (Heat) 67 3% Ti 2.6% SR 399 96.7%(UV 60 s) 0.3% Ti (UV 60 s) 68 5% Ti 2.6% SR 399 94.4% (UV 60 s) 0.3% Ti(UV 60 s) 69 3% Ti 2.6% SR 399 96.2% (UV 60 s) 0.3% Ti (UV 60 s) 70 3%Ti 2.0% SR 399 97.2% (UV 60 s) 0.3% Ti (UV 60 s) 71 2.5% Ti 2% SR 39996.2% 2.5% HEMA 0.06% Irg 184 72 1.5% Ti 2% SR 399 95.3% 1.5% HEMA 0.06%Irg 184 73 1.5% Ti 2% SR 399 97.0% 1.5% HEMA 0.06% Irg 184 9.3 ppm AA13.3% IPA 74 3% Ti 0.0525% PFOFCS 95.6% (UV 60 s) 0.144% CD 1012 1.955%ECHMCHC (UV 60 s) 75 3% Ti 0.0256% PFOFCS 97.0% (UV 60 s) 0.145% CD 10121.978% ECHMCHC (UV 60 s) 76 3% Ti 0.0232% PFOFCS 96.8% (UV 60 s) 0.476%Ti 0.131% CD 1012 1.79% ECHMCHC (UV 60 s) 77 3% Ti 0.051% PFOFCS 97.3%(UV 60 s) 0.139% CD 1012 1.89% ECHMCHC 0.49% H EMA (UV 60 s) 78 3% Ti 00477% PFOFCS 96.9% (UV 60 S) 0 13% CD 1012 1.767% ECHMCHC 0.78% H EMA0.32% Ti (UV 60 s) 79 3% Ti 0.0457% PFOFCS 97.5% (UV 60 s) 0.124% CD1012 0.26% Irg 184 1.685% ECHMCHC 0.746% HEMA 0.306% Ti (UV 60 s) 93 3%Ti 0.11% Irg 184 97.1% (UV 60 s) 0.44% Ti 2% SR 399 (UV 60 s) 81 5% Si0.05% Irg 184 93.8% (UV 60 s) 5% Ti 0.19% SR 399 (UV 60 s) 82 5% Si0.08% Irg 184 92.6% 0.32% Ti 1.44% SR 399 0.005% PFOTCS (UV 60 s) 833.1% Ti-Bu 2% SR 399 96.3% 1.1% HEMA 0.08% Irg 184 13.3% IPA 84 3.1%Ti-Bu 2% SR 399 96.3% 1.1% HEMA 0.08% Irg 184 13.3% IPA 85 4% Ti 2% SR399 97.7% 0.08% Irg 184 0.32% Ti-Bu

In Table 2, Layer 1 refers to the first antireflective coating layer,Layer 2 refers to the second antireflective coating layer. HR-200 refersto a hydrophobic coating layer formed upon Layer 2. Solutions of each ofthe components were prepared and used to form the antireflectivecoatings. For all of the compositions listed in Table 2, the remainderof the composition is made up of 1-methoxy-2-propanol. For example, alisting of 5% Ti, should be understood to mean 5% by weight of Ti and95% by weight of 1-methoxy-2-propanol.

The application of the compositions to the lenses, and the measurementof the transmittance was performed in substantially the same manner asrecited above for Table 1. Curing times are 60 seconds, unless otherwisenoted.

TABLE 2 Visible Light Ex. # Layer 1 Layer 2 Layer 3 Transmittance %Color 86 3% Ti 4.65% Si HR-200  >98% 0.7% Ti 0.05% HC-900 87 1.5% Ti0.46% Ti HR-200 97.3% 454 ppm AA 0.75% GPTMS 300 ppm AS 0.83% TMSPMA92.8% MP 3.4% HC-8 5.6% IPA 0.9% Al (UV 40 s) 88 0.75% Ti 0.46% TiHR-200 96.0% 38 ppm AA 0.75% GPTMS 14.2% MP 0.83% TMSPMA 85% IPA 3.4%HC-8 0.9% Al 89 2% Ti 0.24% Al HR-200 94.7% 100 ppm AA 9.8% HC-8 25.2%MP (UV 60 s) 72.8% IPA (UV 60 s) 90 2% Ti 0.09% Al HR-200 93.5% 100 ppmAA 2.8% SR 368 25.2% MP 0.32% Ti 72.8% IPA 16 ppm AA (UV 60 s) 11.7% IPA(UV 90 s) 91 2% Ti 0.41% Ti HR-200 94.6% 100 ppm AA 0.045% Al 25.2% MP1.4% SR 368 72.8% IPA 0.88% SR 123 0.78% TFEMA 8 ppm AA 5.8% IPA (UV 90s) 92 1% Ti 0.13% Ti HR-200 94.8% 50 ppm AA 0.031% Al 12.6% MP 1.52% SR368 86.4% IPA 0.467% SR 123 (UV 30 s) 0.417% TFEMA (UV 60 s) 93 1% Ti0.21% Ti HR-200 96.7% 50 ppm AA 0.35% Al 12.6% MP 2.4% SR 368 86.4% IPA0.74% SR 123 (UV 40 s) 0.66% TFEMA (UV 60 s) 94 1.54% Ti 0.19% Ti HR-20096.9% 77 ppm AA 0.037% Al 42.3% MP 1.5% SR 368 56.2% IPA 1.14% TMSPMA(UV 30 s) 97.16% MP (UV 180 s)

In Table 3, multiple coating layers are formed on the plastic lens. Forall of the compositions listed in Table 3, the remainder of thecomposition is made up of 1-methoxy-2-propanol. For example, a listingof 5% Ti, should be understood to mean 5% by weight of Ti and 95% byweight of 1-methoxy-2-propanol.

The application of the compositions to the lenses, and the measurementof the transmittance was performed in substantially the same manner asrecited above for Table 1. Curing times are 60 seconds, unless otherwisenoted.

TABLE 3 Ex. # Layer 1 Layer 2 Layer 3 Layer 4 Layer 5  95 2.5% Ti 10% Ti0.7% Ti HR 200 2.5% Si 4.6% Si 0.05% HC 900  96 2% Ti 0.368% Al 26.8%HC-8 HR 200 57 ppm NNDMEA (UV 40 s) 73.2% IPA (UV 30 s)  97 3% Ti 0.055%Irg 184 3% Si 0.055% Irg 184 (UV 70 s) 0.22% Ti (UV 20 s) 0.22% Ti 1% SR399 1% SR 399 0.0125 PFOMA 0.0125% PFOMA (UV 20 s) (UV 70 s)  98 3% Ti0.055% Irg 184 3.7% Natco Si 0.055% Irg 184 (UV 70 s) 0.22% Ti (UV 20 s)0.22% Ti 1% SR 399 1% SR 399 0.0125 PFOMA 0.0125% PFOMA (UV 20 s)  99 3%Ti 0.54% SR 399 0.54% SR 399 0.54% SR 399 (UV 60 s) 0.12% Ti 0.12% Ti0.12% Ti 0.03% Irg 184 0.03% Irg 184 0.03% Irg 184 0.07% PFOMA 0.07%PFOMA 0.07% PFOMA 45.4% AC 45.4% AC 45.4% AC (UV 20 s) (UV 20 s) (UV 20s) 100 3% Ti 0.527% SR 399 0.527% SR 399 0.54% SR 399 0.235% Ti 0.235%Ti 0.12% Ti 0.029% Irg 184 0.029% Irg 184 0.03% Irg 184 0.066% PFOMA0.066% PFOMA 0.07% PFOMA 44.3% AC 44.3% AC 45.4% AC (UV 20 s) (UV 60 s)101 1.5% Ti 0.525% SR 399 3% Si 0.527% SR 399 0.235% Ti 0.23% Ti 0.029%Irg 184 0.024% Irg 184 0.066% PFOMA 0.066% PFOMA 102 3.5% Ti-Bu 0.033%BDKK 0.086% BDKK 0.026% BDKK 0.095% Ti-Bu 0.173% Ti-Bu 0.3% SR 3990.375% SR 399 1% SR 399 0.0037% PFOTCS 2.5% Si 0.0037% FC 430 0.0037%BYK 300 103 5% Ti-Bu 0.086% BDKK 0.086% BDKK 0.026% BDKK (UV 60 s) 0.17%Ti-Bu 0.17% Ti-Bu 0.3% SR 399 1% SR 399 1% SR 399 0.0037% PFOTCS (UV 40s) (UV 50 s) 0.0037% FC 430 0.0037% BYK 300 (UV 60 s) 104 5% Ti-Bu0.033% BDKK 0.086% BDKK 0.026% BDKK (UV 60 s) 0.095% Ti-Bu 0.17% Ti-Bu0.3% SR 399 0.375% SR 399 1% SR 399 0.0037% PFOTCS 2.5% Si (UV 50 s)0.0037% FC 430 (UV 40 s) 0.0037% BYK 300 (UV 60 s) 105 5% Ti-Bu 0.033%BDKK 0.033% BDKK 0.026% BDKK (UV 60 s) 0.095% Ti-Bu 0.095% Ti-Bu 0.3% SR399 0.375% SR 399 0.375% SR 399 0.0037% PFOTCS 2.5% Si 2.5% Si 0.0037%FC 430 (UV 40 s) (UV 50 s) 0.0037% BYK 300 (UV 60 s) 106 5% Ti-Bu 0.086%BDKK 0.033% BDKK 0.026% BDKK (UV 60 s) 0.17% Ti-Bu 0.095% Ti-Bu 0.3% SR399 1% SR 399 0.375% SR 399 0.0037% PFOTCS (UV 50 s) 2.5% Si 0.0037% FC430 (UV 60 s) 0.0037% BYK 300 107 2% Ti 5% Si 5% Ti 5% Si 1% SR 399 (UV50 s) 0.4% SR 399 0.4% Ti 0.17% Ti 0.067% Ti 0.06% Irg 184 0.0416% Irg184 108 2% Ti 5% Si 5% Ti 2% Si 0.2% SR 399 (UV 50 s) 0.4% SR 3990.0346% Ti 0.067% Ti 0.2% SR 399 0.0346% Ti 0.0085% Irg 184 109 2% Ti 1%SR 399 2% Ti 2% Ti 0.1% SR 399 (UV 50 s) 0.17% Ti (UV 30 s) (UV 40 s)0.0416% Irg 184 (UV 50 s) 110 1.5% Ti 2% SR 399 2.75% Ti 1% SR 399 1.4%SR 399 (UV 60 s) 0.5% Si 1% Si 0.062% Irg 184 0.1% Irg 184 0.05% Irg 1840.3% Ti 0.3% Ti 0.3% Ti (UV 60 s) (UV 60 s) 111 1.5% Ti 1% SR 399 2.75%Ti 1% SR 399 1% SR 399 (UV 60 s) 1% Si 1% Si 0.05% Irg 184 0.05% Irg 1840.05% Irg 184 0.21% Ti 0.3% Ti 0.3% Ti (UV 60 s) (UV 60 s) 112 1.5% Ti2% SR 399 2.75% Ti 1% SR 399 1% SR 399 (UV 60 s) 0.5% Si 1% Si 0.05% Irg184 0.1% Irg 184 0.05% Irg 184 0.21% Ti 0.3% Ti 0.3% Ti (UV 60 s) 1131.5% Ti 0.33% SR 399 2.75% Ti 1% SR 399 1% SR 399 (UV 60 s) 3% Si 1% Si0.05% Irg 184 0.017% Irg 184 0.05% Irg 184 0.21% Ti 0.3% Ti 0.3% Ti 1141.5% Ti 0.33% SR 399 2.75% Ti 1% SR 399 0.8% SR 399 3% Si 1% Si 0.035%Irg 184 0.017% Irg 184 0.05% Irg 184 0.17% Ti 0.3% Ti 0.3% Ti 115 1.5%Ti 0.33% SR 399 2.75% Ti 0.33% SR 399 0.8% SR 399 3% Si 3% Si 0.035% Irg184 0.017% Irg 184 0.017% Irg 184 0.17% Ti 0.3% Ti 0.3% Ti 116 2.75% Ti0.596% SR 399 2.75% Ti 2.75% TRi 0.596% SR 399 (UV 50 s) 0.03% Irg 184(UV 50 s) 0.03% Irg 184 0.3% Ti 0.3% Ti 2.2% Si 2.2% Si (UV 50 s) 1172.75% Ti 1.3% SR 399 2.75% Ti 2.75% TRi 0.596% SR 399 (UV 50 s) 0.065%Irg 184 (UV 50 s) 0.03% Irg 184 2.45% Ti 0.3% Ti 0.58% Si 2.2% Si (UV 50s) 118 1.5% Ti 0.596% SR 399 2.75% Ti 1.5% Ti 1.3% SR 399 0.03% Irg 1840.065% Irg 184 0.3% Ti 0.245% Ti 2.2% Si 0.58% Si 119 1.5% Ti 0.596% SR399 2.75% Ti 1.5% Ti 1.4% SR 399 0.03% Irg 184 0.062% Irg 184 0.3% Ti0.3% Ti 2.2% Si 120 1.5% Ti 0.8% SR 399 4% Ti 0.596% SR 399 1.4% SR 399(UV 50 s) 0.035% Irg 184 (UV 50 s) 0.03% Irg 184 0.062% Irg 184 0.17% Ti0.3% Ti 0.3% Ti (UV 50 s) 2.2% Si (UV 50 s) 121 1.5% Ti 1% SR 399 4% Ti0.596% SR 399 1.4% SR 399 (UV 50 s) 0.05% Irg 184 (UV 50 s) 0.03% Irg184 0.062% Irg 184 0.21% Ti 0.3% Ti 0.3% Ti (UV 50 s) 2.2% Si (UV 50 s)122 1.5% Ti 1.4% SR 399 4% Ti 0.596% SR 399 1.4% SR 399 0.062% Irg 1840.03% Irg 184 0.062% Irg 184 0.3% Ti 0.3% Ti 0.3% Ti 2.2% Si (UV 70 s)123 1.5% Ti 0.4% SR 399 4% Ti 0.596% SR 399 1.4% SR 399 0.017% Irg 1840.03% Irg 184 0.062% Irg 184 0.085% Ti 0.3% Ti 0.3% Ti 2.2% Si (UV 70 s)124 2% Ti 1.4% SR 399 4% Ti 0.596% SR 399 0.596% SR 399 (UV 60 s) 0.062%Irg 184 0.03% Irg 184 0.062% Irg 184 0.3% Ti 0.3% Ti 0.3% Ti (UV 60 s)2.2% Si 2.2% Si 125 2% Ti 1% SR 399 4% Ti 0.596% SR 399 0.596% SR 399(UV 60 s) 0.05% Irg 184 0.03% Irg 184 0.062% Irg 184 0.21% Ti 0.3% Ti0.3% Ti (UV 60 s) 2.2% Si 2.2% Si 126 2% Ti 0.596% SR 399 4% Ti 0.596%SR 399 0.596% SR 399 0.03% Irg 184 0.03% Irg 184 0.03% Irg 184 0.3% Ti0.3% Ti 0.3% Ti 2.2% Si 2.2% Si 2.2% Si 127 2% Ti 0.596% SR 399 4% Ti0.596% SR 399 0.596% SR 399 0.03% Irg 184 0.03% Irg 184 0.03% Irg 1840.3% Ti 0.3% Ti 0.3% Ti 2.2% Si 2.2% Si 2.2% Si (UV 60 s) 128 2.75% Ti0.6% SR 399 4% Ti 0.6% SR 399 1.3% SR 399 0.03% Irg 184 0.03% Irg 1840.065% Irg 184 0.3% Ti 0.3% Ti 0.245% Ti 4.4% Si 4.4% Si 0.58% Si 1292.75% Ti 1.4% SR 399 5% Ti 0.4% SR 399 0.6% SR 399 0.062% Irg 184 0.017%Irg 184 0.03% Irg 184 0.31% Ti 0.085% Ti 0.3% Ti 4.4% Si 130 1.75% Ti0.9% SR 399 4% Ti 0.6% SR 399 0.9% SR 399 (UV 60 s) 0.042% Irg 184 (UV60 s) 0.03% Irg 184 0.042% Irg 184 0.19% Ti 0.3% Ti 0.19% Ti (UV 60 s)3.3% Si (UV 60 s) (UV 60 s) 131 1.75% Ti 0.6% SR 399 4% Ti 0.6% SR 3990.9% SR 399 (UV 60 s) 0.03% Irg 184 (UV 60 s) 0.03% Irg 184 0.042% Irg184 0.03% Ti 0.3% Ti 0.19% Ti 3.3% Si 3.3% Si (UV 60 s) (UV 60 s) (UV 60s) 132 1.75% Ti 0.9% SR 399 1.75% Ti 1.75% Ti 0.6% SR 399 0.042% Irg 184(UV 60 s) (UV 60 s) 0.03% Irg 184 0.19% Ti 0.3% Ti 3.3% Si (UV 30 s) 1331.75% Ti 0.9% SR 399 1.75% Ti 1.75% Ti 0.6% SR 399 0.042% Irg 184 (UV 60s) (UV 60 s) 0.03% Irg 184 0.19% Ti 0.3% Ti 3.3% Si (UV 30 s) 134 1.75%Ti 1.4% SR 399 5% Ti 0.6% SR 399 1.4% SR 399 0.3% Ti 0.03% Irg 184 0.3%Ti 0.3% Ti (UV 60 s) 3.3% Si 135 1.75% Ti 1.4% SR 399 5% Ti 0.6% SR 3990.9% SR 399 0.3% Ti 0.03% Irg 184 0.042% Irg 184 0.3% Ti 0.19% Ti 3.3%Si (UV 60 s) 136 1.15% Ti-Bu 1.15% Ti-Bu 3.85% Ti-Bu 1.5% SR 399 0.84%Ti 0.84% Ti 0.25% SR 399 0.1% Irg 184 0.55% SR 399 0.55% SR 399 0.017%Irg 184 50 ppm BYK 300 0.068% Irg 184 0.068% Irg 184 8 ppm BYK 300 50ppm PFOMA 18.5 ppm BYK 300 18.5 ppm BYK 300 8 ppm PFOMA 18.5 ppm PFOMA18.5 ppm PFOMA 137 1.15% Ti-Bu 2.5% Si 1.15% Ti-Bu 3.85% Ti-Bu 1.5% SR399 0.84% Ti (UV 60 s) 0.84% Ti 0.25% SR 399 0.1% Irg 184 0.55% SR 3990.55% SR 399 0.017% Irg 184 50 ppm BYK 300 0.068% Irg 184 0.068% Irg 1848 ppm BYK 300 50 ppm PFOMA 18.5 ppm BYK 300 18.5 ppm BYK 300 8 ppm PFOMA18.5 ppm PFOMA 18.5 ppm PFOMA Visible Light Ex. # Layer 6 Layer 7Transmittance % Color  95 96.8% BLUE  96 96.0%  97 97.2%  98 97.9%  9997.5% 100 96.1% 101 97.0% 102 97.5% 103 98.1% 104 97.9% 105 98.2% 10697.9% 107 97.5% 108 97.7% 109 96.8% 110 96.4% 111 95.1% 112 0.4% SR 39996.1% 0.017% Irg 184 0.085% Ti 113 0.4% SR 399 94.7% 0.017% Irg 1840.085% Ti 114 97.5% 115 97.5% 116 1.3% SR 399 95.6% 0.065% Irg 1840.245% Ti 0.58% Si 117 1.3% SR 399 95.4% 0.065% Irg 184 0.245% Ti 0.58%Si 118 0.596% SR 399 96.7% 0.03% Irg 184 0.3% Ti 2.2% Si 119 0.596% SR399 97.2% 0.03% Irg 184 0.3% Ti 2.2% Si 120 97.6% 121 97.2% 122 0.4% SR399 96.9% 0.017% Irg 184 0.085% Ti 123 98.2% 124 1.4% SR 399 96.4%0.062% Irg 184 0.3% Ti 125 1.4% SR 399 96.5% 0.062% Irg 184 0.3% Ti 1261.4% SR 399 95.3% 0.062% Irg 184 0.3% Ti (UV 60 s) 127 0.4% SR 399 96.1%0.017% Irg 184 0.085% Ti (UV 60 s) 128 1% SR 399 0.1% Ti 97.0% RED 0.05%Irg 184 0.1% PFOTCS 0.21% Ti EtOH (UV 60 s) 129 1.4% SR 399 0.1% Ti96.9% BLUE 0.062% Irg 184 0.1% PFOTCS 0.31% Ti EtOH 130 0.01% PFOA 96.6%BLUE 0.01% PFOMA 0.005% PFOTCS 0.1% Ti 0.007% TBPO 4% MP 95.9% IPA (UV50 s) 131 0.01% PFOA 96.9% YELLOW-RED 0.01% PFOMA 0.005% PFOTCS 0.1% Ti0.007% TBPO 4% MP 95.9% IPA (UV 50 s) 132 0.9% SR 399 96.1% 0.042% Irg184 0.19% Ti (UV 60 s) 133 0.9% SR 399 96.5% 0.042% Irg 184 0.19% Ti (UV60 s) 134 97.6% 135 96.8% 136 95.4% 137 0.085% Ti-Bu 96.4% RED-GREEN0.4% SR 399 0.017% Irg 184

In Table 4, three coating layers are formed on the plastic lens. For allof the compositions listed in Table 4, the remainder of the compositionis made up of 1-methoxy-2-propanol. For example, a listing of 5% Ti,should be understood to mean 5% by weight of Ti and 95% by weight of1-methoxy-2-propanol.

The application of the compositions to the plastic lens, and themeasurement of the transmittance was performed in substantially the samemanner as recited above for Table 1. Curing times are 60 seconds, unlessotherwise noted.

TABLE 4 Visible Light Transmittance Ex. # Layer 1 Layer 2 Layer 3 %Color 138 2% Ti 0.186% Al 26.8% HC-8 94.0% 0.02% NNDMEA (UV 40 s) 73.2%IPA (UV 30 s) 139 1.54% Ti 0.24% Ti 0.3% Al 93.0% 77 ppm AA 0.048% Al(UV 50 s) 42.3% MP 1.94% SR 368 56.2% IPA 1.47% TMSPMA 96.3% MP (UV 180s) 140 2.99% Ti 2.99% Ti 2% SR 399 97.3% 0.28% Irg 184 0.28% Irg 1840.349% Ti (UV 20 s) (UV 20 s) (UV 30 s) 141 0.3% Al 2.99% Ti 2% SR 39995.5% (UV 20 s) 0.28% Irg 184 0.5% SR 306 (UV 40 s) 0.349% Ti (UV 100 s)142 2.97% Ti 2.99% Ti 2% SR 399 93.6% 0.29% Irg 184 0.28% Irg 184 0.5%SR 306 1% SR 368 0.349% Ti (UV 30 s) 143 1.69% Ti 2.99% Ti 2% SR 39994.5% 0.168% Irg 184 0.28% Irg 184 0.5% SR 306 0.58% SR 368 0.349% Ti144 3.25% Ti 3.25% Ti 2% SR 399 93.0% GREENISH 0.1% Irg 184 0.1% Irg 1840.4% Ti BLUE (UV 30 s, (UV 30 + 60 s) 0.04% Irg 184 350 rpm) 0.1% BYK300 (UV 60 s) 145 0.5% Ti 2.46% Ti 0.53% Ti 97.3% 0.25% Irg 184 0.197%Irg 184 0.1% Irg 184 0.5% Al 0.157% SR 313 0.85% SR 313 4.67% SR 39944.3% AC 1.38% SR 399 146 3% Ti 3% HEMA 0.06% Irg 184 97.4% (UV 60 s)0.25% Ti 0.32% Ti 0.33% TEA 2% SR 399 0.02% Eiosin (UV 60 s) (UV 60 s)147 3% HEMA 3% Ti 0.06% Irg 184 97.5% 0.25% Ti (UV 60 s) 0.32% Ti 0.33%TEA 2% SR 399 0.02% Eiosin (UV 60 s) (UV 60 s) 148 3% Ti 2.5% HEMA 0.06%Irg 184 97.4% (UV 60 s) 0.25% T 770 0.32% Ti 0.5% Ti 2% SR 399 (UV 60 s)149 3% Ti 2.5% HEMA 0.06% Irg 184 97.8% (UV 60 s) 0.25% T 770 0.32% Ti0.5% Ti 2% SR 399 (UV 60 s) 150 3% Ti 0.037% PFOFCS 2% SR 399 94.4% 0.1%CD 1012 0.32% Ti 0.21% Irg 194 0.06% Irg 184 1.35% ECHMCHC (UV 60 s)0.6% HEMA 0.246% Ti 1% SR 399 151 1.3% HEMA 0.05% BDKK 0.164% HEMA 98.5%0.96% SR 640 0.57% SR 399 0.05% PFOTCS 3.576% Ti-Bu 0.43% HEMA 97.86%IPA 5.66% Si 1.93% MP 152 3.5% Ti-Bu 0.087% BDKK 0.035% BDKK 97.0%0.095% Ti-Bu 0.4% SR 399 1% SR 399 0.005% PFOTCS 2.9% Si 0.005% FC 4300.005% BYK 300 153 3.5% Ti-Bu 0.043% BDKK 0.174% BDKK 94.0% BLUE 0.047%Ti-Bu 0.173% Ti-Bu 0.5% SR 399 2% SR 399 1.45% Si 154 5% Ti-Bu/ 0.033%BDKK 0.026% BDKK 97.2% 5% Ti-Bu 0.095% Ti-Bu 0.3% SR 399 0.375% SR 3990.0037% PFTOCS 2.5% Si 0.0037% FC 430 0.0037% BYK 300 155 1.15% Ti-Bu1.15% Ti-Bu 1.5% SR 399 95.7% YELLOW 0.84% Ti 0.84% Ti 0.1% Irg 1840.55% SR 399 0.55% SR 399 50 ppm BYK 300 0.068% Irg 184 0.068% Irg 18450 ppm PFOMA 18.5 ppm BYK 18.5 ppm BYK 300 300 18.5 ppm PFOMA 18.5 ppmPFOMA

In Table 5, Layer 1 refers to the first antireflective coating layer,Layer 2 refers to an intermediate silicon layer, and Layer 3 refers tothe second antireflective coating layer. Solutions of each of thecomponents were prepared and used to form the antireflective coatings.For all of the compositions listed in Table 5, the remainder of thecomposition is made up of 1-methoxy-2-propanol. For example, a listingof 5% Ti, should be understood to mean 5% by weight of Ti and 95% byweight of 1-methoxy-2-propanol.

The plastic eyeglass lens was coated using different coatingcompositions. The “Layer 1” composition was added to a surface of theeyeglass lens and the eyeglass lens was rotated on a lens spin-coatingapparatus. After the Layer 1 composition was spread onto the eyeglasslens surface the solvent was allowed to substantially evaporate and theremaining composition was subjected to ultraviolet light from thegermicidal lamp from the previously described coating unit for about 60seconds, unless otherwise noted. Layer 2 (the silicon layer) was addedto the eyeglass lens after the Layer 1 composition was cured. Curingtime of the second layer is 60 seconds, unless otherwise noted. TheLayer 2 composition was spread onto the eyeglass lens surface and theeyeglass lens was spun until the solvent was substantially evaporated.The Layer 3 composition was added to the eyeglass lens after the Layer 2composition was dried. The eyeglass lens was spun on a lens spin-coatingapparatus until the solvent was substantially evaporated. Layer 3 wasthen cured by the application of ultraviolet light from the germicidallamp from the previously described coating unit. Curing time for thethird layer is 60 seconds, unless otherwise noted. From one to fouradditional layers were added to the top of the antireflective stack. The% transmittance refers to the amount of light transmitted through thelens after the final layer was cured. The transmittance was measured asdescribed above.

TABLE 5 Layer Layer Visible Light Ex. # Layer 1 Layer 2 Layer 3 Layer 4Layer 5 6 7 Transmittance % Color 156 1.5% Ti 1.5% Si 0.257% Ti HR 20096.0% BROWN 454 ppm AA 98.5% IPA 0.257% GPTMS GOLD 300 ppm AS (UV 40 s)2.85% HC-8 92.8% MP 0.5% Al 5.6% IPA 0.26% TMSPMA (UV 40 s) (UV 120 s)157 1.5% Ti 1.5% Si 0.46% Ti HR 200 94.4% 76 ppm AA 98.5% IPA 0.75%GPTMS 28.4% MP (UV 40 s) 0.83% TMSPMA 70.1% IPA 3.4% HC-8 (UV 60 s) 0.9%Al (UV 120 s) 158 3% Ti 1.5% Si 0.055% Irg 184 97.4% (UV 70 s) 0.22% Ti0.22% Ti 1% SR 399 1% SR 399 0.0125% PFOMA 0.0125% PFOMA (UV 70 s) (UV60 s) 159 3% Ti 1.5% Si 0.025% Irg 184 1.5% Si 0.025% Irg 184 94.5%YELLOW (UV 60 s) (UV 20 s) 0.14% Ti 0.14% Ti 0.96% SR 399 0.96% SR 399(UV 20 s) (UV 60 s) 160 3% Ti 1.5% Si 1.5% Si 0.08% Irg 184 97.4    RED(UV 60 s) 0.32% Ti 1.44% SR 399 0.005% PFOTCS (UV 60 s) 161 3% Ti 1.5%Si 1.5% Si 0.08% Irg 184 97.3    (UV 60 s) (UV 60 s) 0.32% Ti 1.44% SR399 0.005% PFOTCS (UV 60 s) 162 3% Ti 1.5% Si 1.5% Si 0.11% Irg 18493      (UV 60 s) (UV 60 s) 0.44% Ti 2% SR 399 0.005% PFOTCS (UV 60 s)163 3% Ti 1.5% Si 1.5% Si 0.055% Irg 184 95.3% 0.22% Ti 1% SR 3990.0125% PFOTCS 164 3% Ti 1.5% Si 1.5% Si 0.055% Irg 184 0.055% Irg 18494.6% 0.22% Ti 0.22% Ti 1% SR 399 1% SR 399 0.0125% PFOTCS 0.0125%PFOTCS 165 3% Ti 2.4% Si 2.4% Si 0.08% Irg 184 97.6% 0.53% SR 640 0.97%SR 640 0.97% SR 640 0.32% Ti 70 ppm FC 430 70 ppm FC 430 70 ppm FC 4301.44% SR 399 (UV 60 s) 0.005% PFOTCS 166 3% Ti 5% Si 0.33% SR 399 0.527%SR 399 97.3% 0.07% Ti 0.23% Ti 0.018% Irg 184 0.029% Irg 184 0.07% PFOMA0.066% PFOMA 167 3.85% Ti-Bu 1% SR 399 1% SR 399 1.15% Ti-Bu 1.739% SR399 96.7% 0.25% SR 399 2.4% Si 2.4% Si 0.84% Ti 0.12% Irg 184 0.017% Irg184 0.55% SR 399 60 ppm BYK 300 8 ppm BYK 300 0.068% Irg 184 60 ppmPFOMA 8 ppm PFOMA 18.5 ppm BYK 300 18.5 ppm PFOMA (UV 60 s)

In Table 6, Layer 1 refers to the first antireflective coating layer,Layer 2 refers to an intermediate silicon layer, and Layer 3 refers tothe second antireflective coating layer. Solutions of each of thecomponents were prepared and used to form the antireflective oatings.For all of the compositions listed in Table 6, the remainder of thecomposition is made up of 1-methoxy-2-propanol. For example, a listingof 5% Ti, should be understood to mean 5% by weight of Ti and 95% byweight of 1-methoxy-2-propanol.

The plastic eyeglass lens was coated using different coatingcompositions. The “Layer 1” composition was added to a surface of theeyeglass lens and the eyeglass lens was rotated on a lens spin-coatingapparatus. The first coating layer was formed by a two step procedure.In the first step, a solution of Ti was added to the plastic lens andallowed to dry. In the second step, an additional solution of Ti wasadded to the plastic lens and allowed to dry. The % of Ti used for thefirst and second steps are respectively listed in the “Layer 1” column.The Layer 1 composition was allowed to substantially evaporate and theremaining composition was subjected to ultraviolet light from thegermicidal lamp from the previously described coating unit for about 60seconds, unless otherwise noted. Layer 2 (the silicon layer) was addedto the eyeglass lens after the Layer 1 composition was cured. The Layer2 composition was spread onto the eyeglass lens surface and the eyeglasslens was spun until the solvent was substantially evaporated. The Layer3 composition was added to the eyeglass lens after the Layer 2composition was dried. The eyeglass lens was spun on a lens spin-coatingapparatus until the solvent was substantially evaporated. Layer 3 wasthen cured by the application of ultraviolet light from the germicidallamp from the previously described coating unit. Curing time was 60seconds, unless otherwise noted. From one to four additional layers wereadded to the top of the antireflective stack. The % transmittance refersto the amount of light transmitted through the lens after the finallayer was cured. The transmittance was measured as described above.

TABLE 6 Visible Light Ex. # Layer 1 Layer 2 Layer 3 Transmittance %Color 168 1.5% Ti/3% Ti 3% Si 0.08% Irg 184 97.6% BLUE (UV 40 s/40 s)0.32% Ti 1.45% SR 399 (UV 60 s) 169 3% Ti/1.5% Ti 3% Si 0.08% Irg 18498.3% PURPLE (UV 40 s/40 s) 0.32% Ti 1.45% SR 399 (UV 60 s) 170 5% Ti/3%Ti 3% Si 0.08% Irg 184 92.2% (UV 40 s/40 s) 0.32% Ti 1.45% SR 399 (UV 90s) 171 3% Ti/5% Ti 3% Si 0.08% Irg 184 94.1% (UV 40 s/40 s) 0.32% Ti1.45% SR 399 (UV 90 s) 172 1.5% Ti/1.5% Ti 3% Si 0.08% Irg 184 97.6% (UV60 s/60 s) 0.32% Ti 1.45% SR 399 173 3% Ti/3% Ti 3% Si 0.08% Irg 18497.6% (UV 60 s/60 s) (UV 30 s) 0.32% Ti 1.45% SR 399

In Table 7, Layer 1 refers to the first antireflective coating layer,Layer 2 refers to an intermediate silicon layer, and Layer 3 refers tothe second antireflective coating layer. Solutions of each of thecomponents were prepared and used to form the antireflective coatings.For all of the compositions listed in Table 7, the remainder of thecomposition is made up of 1-methoxy-2-propanol. For example, a listingof 5% Ti, should be understood to mean 5% by weight of Ti and 95% byweight of 1-methoxy-2-propanol.

The application of the compositions to the plastic lens, and themeasurement of the transmittance was performed in substantially the samemanner as recited above for Table 1. Curing time was 60 seconds, unlessotherwise noted.

TABLE 7 Visible Light Ex. # Layer 1 Layer 2 Layer 3 Transmittance %Color 174 3% Ti 6% Si 0.8% Ti 96.0% 0.8% GPTMS 0.8% TMSPMA 175 5.2% Ti5% Si 0.75 Ti 96.6% 0.97% HC 8558 0.75% HC 8558 176 3.75% Ti 3% Si0.257% Ti 98.3% RED 0.019% AA 97% IPA 0.257% GPTMS 71% MP 2.85% HC-825.25% IPA 0.5% Al 177 3.75% Ti 1.5% Si 0.257% Ti 95.6% RED 0.019% AA98.5% IPA 0.257% GPTMS 71% MP 2.85% HC-8 25.25% IPA 0.5% Al 178 7.5% Ti1.5% Si 0.257% Ti 96.0% RED 0.038 AA 98.5% IPA 0.257% GPTMS 45.3% MP2.85% HC-8 47.2% IPA 0.5% Al 179 3% Ti 5% Si 0.16% Ti 98.1% 1% SR 399 50ppm PFOFCS 180 3% Ti 6.94% Nalco Si 0.16% Ti 95.7% 1% SR 399 50 ppmPFOFCS 181 3% Ti 6.94% Nalco Si 0.317% Ti 93.0% 2% SR 399 0.08% Irg 1840.06% PFOFCS 182 3% Ti 3% Si 0.11% Irg 184 93.0% BLUE 0.44% Ti 2% SR 399183 3% Ti 3% Si 0.05% Irg 184 94.3% GOLD 0.02% Ti 0.9% SR 399 184 3% Ti4% Si 0.05% Irg 184 96.4% 0.2% Ti 0.9% SR 399 185 3% Ti 5% Si 0.05% Irg184 97.9% 0.2% Ti 0.9% SR 399 186 3% Ti 4% Si 0.079% Irg 184 97.0%0.322% Ti 1.45% Sr 399 187 3% Ti 4% Si 0.079% Irg 184 96.8% 0.322% Ti1.45% Sr 399 188 3% Ti 3% Si 0.079% Irg 184 97.3% 0.322% Ti 1.45% Sr 399189 3% Ti 3% Si 0.08% Irg 184 97.7% 0.32% Ti 1.44% SR 399 0.005% PFOA190 3% Ti 3% Si 0.08% Irg 184 97.6% 0.32% Ti 1.44% SR 399 0.047% PFOMA191 3% Ti 3% Si 0.08% Irg 184 97.8% 0.32% Ti 1.44% SR 399 0.005% PFOTCS192 3% Ti 5% Si 0.08% Irg 184 95.7% 0.32% Ti 1.44% SR 399 0.005% PFOTCS193 1.5% Ti 5% Si 0.08% Irg 184 94.6% 0.32% Ti 1.45% SR 399 194 1.5% Ti3% Si 0.08% Irg 184 95.1% 0.32% Ti 1.45% SR 399 195 2% Ti 3% Si 0.08%Irg 184 95.6% 0.32% Ti 1.45% SR 399 196 2% Ti 3% Si 0.08% Irg 184 96.0%0.03% BYK 300 0.32% Ti 1.45% SR 399 197 3% Ti 1.5% Si 0.11% Irg 18497.2% 0.44% Ti 2% SR 399 0.005% PFOMA 198 3% Ti 1.5% Si 0.08% Irg 18495.0% 0.32% Ti 1.44% SR 399 0.005% PFOMA 199 3% Ti 1.5% Si 0.11% Irg 18496.7% 0.44% Ti 2% SR 399 0.005% PFOMA 200 3% Ti 3% Si 0.08% Irg 18497.5% 0.53% SR 640 0.32% Ti 1.44% SR 399 0.005% PFOTCS 201 3% Ti 3% Si0.08% Irg 184 97.1% 0.32% Ti 1.44% SR 399 0.005% PFOTCS 202 3% Ti 3% Si0.08% Irg 184 97.8% 0.5% SR 640 0.32% Ti 1.44% SR 399 0.005% PFOTCS 2033% Ti 3% Si 0.08% Irg 184 97.8% 0.53% SR 640 0.53% SR 640 0.32% Ti 70ppm FC 430 70 ppm FC 430 1.44% SR 399 0.005% PFOTCS 204 3% Ti 5% Si1.44% SR 399 97.4% 0.32% Ti 0.08% Irg 184 0.005% PFOTCS 205 3.85% Ti-Bu5% Si 1.56% Ti-Bu 95.8% YELLOW 0.25% SR 399 0.5% SR 399 0.017% Irg 1840.033% Irg 184 8 ppm BYK 300 16 ppm BYK 300 8 ppm PFOMA 16 ppm PFOMA

Table 8 refers to a series of experiments using an in-mold curingprocess. In the in-mold process the layers are built in the oppositemanner than they are built upon the plastic lens. Layer 1, thus, refersto the second antireflective coating layer, Layer 2 refers to the firstantireflective coating layer, and Layer 3 refers to an adhesion layer.Solutions of each of the components were prepared and used to form theantireflective coatings. For all of the compositions listed in Table 8,the remainder of the composition is made up of 1-methoxy-2-propanol. Forexample, a listing of 5% Ti, should be understood to mean 5% by weightof Ti and 95% by weight of 1-methoxy-2-propanol.

A casting face of a mold was coated using the different coatingcompositions. The “Layer 1” composition was added to a surface of themold and the mold was rotated on a lens spin-coating apparatus. TheLayer 1 composition was allowed to substantially evaporate and theremaining composition was subjected to ultraviolet light from thegermicidal lamp from the previously described coating unit for about 60seconds, unless otherwise noted. Layer 2 was added to the eyeglass lensafter the Layer 1 composition was cured. The Layer 2 composition wasspread onto the eyeglass lens surface and the eyeglass lens was spununtil the solvent was substantially evaporated. Layer 2 was then curedby the application of ultraviolet light from the germicidal lamp fromthe previously described coating unit. Curing time was 60 seconds,unless otherwise noted. Layer 3 was then added to the antireflectivestack. Layer 3 was added to the mold, spun dried and cured. Curing timewas 60 seconds, unless otherwise noted.

A pair of coated molds was then used to in a mold assembly to form aplastic lens. After the lens was formed, the lens was removed from moldassembly and the % transmittance of the plastic lens measured. Thetransmittance was measured as described above.

TABLE 8 Visible Light Ex. # Layer 1 Layer 2 Layer 3 Transmittance %Color 206 1% SR 399 92.5% 0.059% Irg 184 0.007% PFOMA 207 1% SR 39992.5% 0.059% Irg 184 0.007% PFOMA 0.0062% Q4DC 208 1% SR 399 1.44% SR399 3% Ti 97.0% GOLD 0.059% Irg 184 0.08% Irg 184 0.007% PFOMA 0.32% Ti0.0062% Q4DC 0.005% PFOTCS 209 2.58% SR 399 4% Ti-Bu 2.58% SR 399 94.5%0.147% Irg 184 1.2% HEMA 0.147% Irg 184 0.32% Ti-Bu 14% IPA 0.32% Ti-Bu(UV 60 s) (UV 60 s) (UV 60 s) 210 2.2% SR 399 2.2% SR 399 2.2% SR 39997.7% BLUISH RED 0.126% Irg 184 0.126% Irg 184 0.126% Irg 184 0.003%PFOMA 0.003% PFOMA 0.003% PFOMA 211 2.2% SR 399 4% Ti-Bu 97.7% 0.126%Irg 184 1.2% HEMA 0.0031% PFOMA 14% IPA 212 2.2% SR 399 4% Ti-Bu 97.1%0.14% D 1173 1.2% HEMA 14% IPA 213 22% SR 399 2.022% Ti-Bu 1% Si >95.50.14% D 1173 2.026% HEMA 2.2% SR 399 (UV 70 s) (UV 70 s) 0.165% Ti-Bu0.14% D1173 (UV 70 s) 214 2.06% SR 399 3.62% Ti-Bu 2.06% SR 399 97.0%RED GOLD 0.136% D1173 1.5% HEMA 0.136% D1173 0.95% HEMA (UV 90 s) 0.95%HEMA (UV 90 s) (UV 90 s) 215 2% SR 399 3.62% Ti-Bu 2.12% SR 399 97.0%0.145% D1173 1.5% HEMA 0.14% D1173 (UV 90 s) (UV 90 s) 0.5% HEMA (UV 90s) 216 2.2% SR 399 3.6% Ti-Bu 2.2% SR 399 94.7% 0.117% BDK 1.5% HEMA0.117% BDK (UV 90 s) 217 2.66% SR 399 3.6% Ti-Bu 2.66% SR 399 95.0%0.114% BDK 1.5% HEMA 0.114% BDK (UV 90 s) 218 2.886% SR 399 3.6% Ti-Bu2.886% SR 399 94.5% 0.124% BDK 1.5% HEMA 0.124% BDK 219 2.2% SR 3993.46% Ti-Bu 2.2% SR 399 97.7% 0.19% BDK (UV 60 s) 0.19% BDK (UV 60 s)(UV 60 s) 220 2.2% SR 399 3.7% Ti-Bu 2.2% SR 399 97.6% 0.19% BDK 0.005%PFOMA 0.19% BDK (UV 60 s) 0.003% BDK (UV 60 s) 221 2.2% SR 399 3.7%Ti-Bu 2.2% SR 399 98.0% 0.19% BDK 0.0247% BDK 0.19% BDK 0.028% PFOTCS0.091% HEMA 222 2.2% SR 399 3.7% Ti-Bu 2.2% SR 399 98.2% 0.19% BDK0.0123% BDK 0.19% BDK (UV 60 s) 0.014% PFOTCS 0.045% HEMA 223 0.028% BDK1.3% HEMA 0.19% BDK 95.2% 0.32% SR 399 0.96% SR640 2.2% SR 399 0.24%HEMA 3.576% Ti-Bu 0.01% HEMA 3.2% Si 0.03% PFOTCS 5.9% IPA 91.7% MP 2241.5% SR 399 3.849% Ti 1.04% Ti 94.7% 0.1% Irg 184 0.25% SR 399 0.5% SR399 0.005% BYK 300 0.001 6% Irg 184 0.033% Irg 184 0.005% PFOMA 8 ppmBYK 300 16 ppm BYK 300 8 ppm PFOMA 16 ppm PFOMA

In Table 9, multiple coating layers are formed on the casting surface ofthe molds prior to use. For all of the compositions listed in Table 9,the remainder of the composition is made up of 1-methoxy-2-propanol. Forexample, a listing of 5% Ti, should be understood to mean 5% by weightof Ti and 95% by weight of 1-methoxy-2-propanol.

The application of the compositions to the lenses, and the measurementof the transmittance was performed in substantially the same manner asrecited above for Table 8. Curing times were 60 seconds, unlessotherwise noted.

TABLE 9 Ex. # Layer 1 Layer 2 Layer 3 Layer 4 Layer 5 225 0.5% SR 3991.44% SR 399 3% Ti HC-8 0.02% Irg 184 0.32% Ti 0.02% PFOMA 0.08% Irg 1840.005% PFOTCS 226 0.05% BDKK 1.3% HEMA 0.19% BDKK 0.164% HEMA 0.57% SR399 0.96% SR 640 2.2% SR 399 0.05% PFOTCS 0.43% HEMA 3.576% Ti-Bu 0.01%HEMA 97.86% IPA 5.66% Si 0.03% PFOTCS 1.93% MP 5.9% IPA 91.7% MP 2270.01% FC 725 0.0134% Irg 184 0.6% SR 399 0.9% SR 399 4% Ti 40% IPA0.033% D 1173 0.03% Irg 184 0.04% Irg 184 0.015% FC 171 0.527% SR 3990.3% Ti 0.19% Ti 50% AC 0.178% SR 423 3.3% Si (UV 60 s) 0.088% SR 90030.008% CD 540 0.06% ppm TPB (UV 60 s) 228 0.01% FC 725 0.0134% Irg 1841.4% SR 399 4% Ti 0.6% SR 399 0.015% FC 171 0.033% D 1173 0.1% Irg 1840.04% TX-100 0.03% Irg 184 50% IPA 0.527% SR 399 0.3% Ti 0.3% Ti 50% AC0.178% SR 423 3.3% Si 0.088% SR 9003 0.008% CD 540 0.06 ppm TPB 2290.01% FC 725 1% SR 399 0.9% SR 399 4% Ti 0.9% SR 399 50% IPA 0.5% SR 3680.042% Irg 184 0.04% TX-100 0.042% Irg 184 0.015% FC 171 0.01% Irg 1840.19% Ti 0.19% Ti 50% AC 0.05% TPB 230 1.5% SR 399 1.04% Ti 3.849% Ti1.5% SR 399 0.1% Irg 184 0.5% SR 399 0.25% SR 399 0.1% Irg 184 0.005%BYK 300 0.033% Irg 184 0.0016% Irg 184 0.005% BYK 300 0.005% PFOMA 16ppm BYK 300 8 ppm BYK 300 0.005% PFOMA 16 ppm PFOMA 8 ppm PFOMA 231 1.5%SR 399 2.5% Si/2.5% Si 1.04% Ti 1.04% Ti 3.849% Ti 0.1% Irg 184 0.5% SR399 0.5% SR 399 0.25% SR 399 0.005% BYK 300 0.033% Irg 184 0.033% Irg184 0.0016% Irg 184 0.005% PFOMA 16 ppm BYK 300 16 ppm BYK 300 8 ppm BYK300 16 ppm PFOMA 16 ppm PFOMA 8 ppm PFOMA 232 1.5% SR 399 1.04% Ti3.849% Ti 0.3% Ti 2.5% Si 0.1% Irg 184 0.5% SR 399 0.25% SR 399 1.4% SR399 0.005% BYK 300 0.033% Irg 184 0.0016% Irg 184 0.06% Irg 184 0.005%PFOMA 16 ppm BYK 300 8 ppm BYK 300 16 ppm PFOMA 8 ppm PFOMA VisibleLight Ex. # Layer 6 Layer 7 Transmittance % Color 225 96.7% 226 94.7%227 0.01% FC 725 97.7% 40% IPA 0.015% FC 171 50% AC 228 0.0134% Irg 18497.5% 0.033% D 1173 0.527% SR 399 0.178% SR 423 0.088% SR 9003 0.008% CD540 0.06 ppm TPB 229 1% SR 399 98.0% 0.5% SR 368 0.01% Irg 184 0.05% TPB230 97.5% 231 1.04% Ti 95.5% 0.5% SR 399 0.033% Irg 184 16 ppm BYK 30016 ppm PFOMA 232 1.04% Ti 97.0% 0.5% SR 399 0.033% Irg 184 16 ppm BYK300 16 ppm PFOMA

Further modifications and alternative embodiments of various aspects ofthe invention will be apparent to those skilled in the art in view ofthis description. Accordingly, this description is to be construed asillustrative only and is for the purpose of teaching those skilled inthe art the general manner of carrying out the invention. It is to beunderstood that the forms of the invention shown and described hereinare to be taken as the presently preferred embodiments. Elements andmaterials may be substituted for those illustrated and described herein,parts and processes may be reversed, and certain features of theinvention may be utilized independently, all as would be apparent to oneskilled in the art after having the benefit of this description of theinvention. Changes may be made in the elements described herein withoutdeparting from the spirit and scope of the invention as described in thefollowing claims.

What is claimed is:
 1. A method for forming an at least partiallyantireflective coating on a visible light-transmitting substrate,comprising: applying a first composition to at least one surface of thevisible light-transmitting substrate to form a first coating layer, thefirst composition comprising a first metal alkoxide; applying a secondcomposition to the first coating layer, the second compositioncomprising, an ethylenically substituted monomer and a second metalalkoxide, wherein the second composition is curable by the applicationof ultraviolet light; and directing ultraviolet light toward the secondcomposition, wherein the ultraviolet light initiates curing of thesecond composition to form a second coating layer.
 2. The method ofclaim 1, wherein the first composition is curable by the application ofultraviolet light.
 3. The method of claim 1, further comprisingdirecting ultraviolet light toward the first composition, wherein theultraviolet light initiates curing of the first composition to form thefirst coating layer.
 4. The method of claim 1, further comprisingheating the first composition, wherein heating the first compositioninitiates curing of the first composition to form the first coatinglayer.
 5. The method of claim 1, wherein the first coating layer has anindex of refraction that is greater than an index of refraction of thevisible light-transmitting substrate.
 6. The method of claim 1, whereinthe second coating layer has an index of refraction that is less than anindex of refraction of the first coating layer.
 7. The method of claim1, wherein the first coating layer has an index of refraction that isgreater than an index of refraction of the visible light-transmittingsubstrate, and wherein the second coating layer has an index ofrefraction that is less than an index of refraction of the first coatinglayer.
 8. The method of claim 1, wherein the first and second metalalkoxides have the general formula M (Y)_(p) wherein M is titanium,aluminum, zirconium, boron, tin, indium, antimony, or zinc, Y is aC₁-C₁₀ alkoxy or acetylacetonate, and p is an integer equivalent to thevalence of M.
 9. The method of claim 1, wherein the first and secondmetal alkoxides have the general formula Ti(OR)₄, where R is a C₁-C₁₀alkyl.
 10. The method of claim 1, wherein the first and second metalalkoxides are titanium methoxide, titanium ethoxide, titaniumisopropoxide, titanium butoxide, or titanium allylacetoacetatetriisopropoxide.
 11. The method of claim 1, wherein the firstcomposition further comprises a photoinitiator.
 12. The method of claim1, wherein the first composition further comprises colloidal silica. 13.The method of claim 1, wherein the visible light-transmitting substrateis a plastic eyeglass lens.
 14. The method of claim 1, wherein thevisible light transmitting substrate is a glass lens.
 15. The method ofclaim 1, wherein the first composition further comprises a coinitiator.16. The method of claim 1, wherein the first composition furthercomprises an ethylenically substituted monomer.
 17. The method of claim1, wherein the first composition further comprises an organic solvent.18. The method of claim 1, wherein the second composition furthercomprises a silane monomer.
 19. The method of claim 1, wherein thesecond composition further comprises a fluoroacrylate.
 20. The method ofclaim 1, wherein the second metal alkoxide is a titanium alkoxide. 21.The method of claim 1, wherein the second metal alkoxide is an aluminumalkoxide.
 22. The method of claim 1, wherein the second compositionfurther comprises a photoinitiator.
 23. The method of claim 1, whereinthe ethylenically substituted monomer comprises dipentaerythritoltetracrylate.
 24. The method of claim 1, wherein the second compositionfurther comprises an organic solvent.
 25. The method of claim 1, furthercomprising forming a hardcoat layer on the surface of the visiblelight-transmitting substrate prior to applying the first composition tothe surface of the visible light-transmitting substrate.
 26. The methodof claim 24, wherein forming a hardcoat layer on the surface of thevisible light-transmitting substrate comprises: applying an ultravioletlight curable hardcoat composition to the surface of the visiblelight-transmitting substrate; and directing ultraviolet light toward thehardcoat composition, wherein the ultraviolet light initiates curing ofthe hardcoat composition to form the hardcoat layer.
 27. The method ofclaim 1, wherein applying the hardcoat composition to the surface of thevisible light-transmitting substrate comprises rotating the visiblelight-transmitting substrate while directing the hardcoat compositiontoward the visible light-transmitting substrate.
 28. The method of claim1, wherein applying the first composition comprises directing the firstcomposition toward the visible light-transmitting substrate whilerotating the visible light-transmitting substrate.
 29. The method ofclaim 1, wherein applying the second composition comprises directing thesecond composition toward the visible light-transmitting substrate whilerotating the visible light-transmitting substrate.
 30. The method ofclaim 1, wherein ultraviolet light is directed toward the secondcomposition for a time of less than about 90 seconds.
 31. The method ofclaim 1, further comprising heating the visible light-transmittingsubstrate at a temperature of between about 40° C. and about 140° C. fora time of less than about 10 minutes.
 32. The method of claim 1, whereinapplying the first composition to the visible light-transmittingsubstrate comprises: applying a first portion of the first compositionto the visible light-transmitting substrate; drying the first portion ofthe first composition; applying a second portion of the firstcomposition to the dried first portion; and drying the second portion ofthe first composition.
 33. The method of claim 1, wherein theultraviolet light is produced by a germicidal lamp.
 34. The method ofclaim 1, wherein the ultraviolet light is produced by a flash lamp. 35.The method of claim 1, further comprising forming a hardcoat layer uponthe surface of the visible light transmitting substrate prior to formingthe first coating layer.
 36. The method of claim 1, wherein the firstcomposition is applied to a front surface of the visiblelight-transmitting substrate.
 37. The method of claim 1, wherein thefirst composition is applied to a back surface of the visiblelight-transmitting substrate.
 38. The method of claim 1, wherein thefirst composition is applied to a front surface and a back surface ofthe visible light-transmitting substrate.
 39. The method of claim 1,wherein a thickness of the first coating layer and the second coatinglayer, combined, is less than about 500 nm.
 40. The method of claim 1,wherein the antireflective coating is formed in less than about 10 min.41. A plastic eyeglass lens comprising an at least partiallyantireflective coating, formed by the method, comprising: applying afirst composition to at least one surface of a non-coated plasticeyeglass lens to form a first coating layer, the first compositioncomprising a first metal alkoxide; applying a second composition to thefirst coating layer, the second composition comprising an ethylenicallysubstituted monomer and a second metal alkoxide, wherein the secondcomposition is curable by the application of ultraviolet light; anddirecting ultraviolet light toward the second composition, wherein theultraviolet light initiates curing of the second composition to form asecond coating layer.
 42. The method of claim 41, wherein the firstcomposition is curable by the application of ultraviolet light.
 43. Themethod of claim 41, further comprising directing ultraviolet lighttoward the first composition, wherein the ultraviolet light initiatescuring of the first composition to form the first coating layer.
 44. Themethod of claim 41, further comprising heating the first composition,wherein heating the first composition initiates curing of the firstcomposition to form the first coating layer.
 45. The method of claim 41,wherein the first coating layer has an index of refraction that isgreater than an index of refraction of the plastic eyeglass lens. 46.The method of claim 41, wherein the second coating layer has an index ofrefraction that is less than an index of refraction of the first coatinglayer.
 47. The method of claim 41, wherein the first coating layer hasan index of refraction that is greater than an index of refraction ofthe plastic eyeglass lens, and wherein the second coating layer has anindex of refraction that is less than an index of refraction of thefirst coating layer.
 48. The method of claim 41, wherein the first andsecond metal alkoxides have the general formula M(Y)_(p) wherein M istitanium, aluminum, zirconium, boron, tin, indium, antimony, or zinc, Yis a C₁-C₁₀ alkoxy or acetylacetonate, and p is an integer equivalent tothe valence of M.
 49. The method of claim 41, wherein the first andsecond metal alkoxides have the general formula Ti(OR)₄, where R is aC₁-C₁₀ alkyl.
 50. The method of claim 41, wherein the first and secondmetal alkoxides are titanium methoxide, titanium ethoxide, titaniumisopropoxide, titanium butoxide, or titanium allylacetoacetatetriisopropoxide.
 51. The method of claim 41, wherein the firstcomposition further comprises a photoinitiator.
 52. The method of claim41, wherein the first composition further comprises colloidal silica.53. The method of claim 41, wherein the first composition furthercomprises a coinitiator.
 54. The method of claim 41, wherein the firstcomposition further comprises an ethylenically substituted monomer. 55.The method of claim 41, wherein the first composition further comprisesan organic solvent.
 56. The method of claim 41, wherein the secondcomposition further comprises a silane monomer.
 57. The method of claim41, wherein the second composition further comprises a fluoroacrylate.58. The method of claim 41, wherein the second metal alkoxide is atitanium alkoxide.
 59. The method of claim 41, wherein the second metalalkoxide is an aluminum alkoxide.
 60. The method of claim 41, whereinthe second composition further comprises a photoinitiator.
 61. Themethod of claim 41, wherein the ethylenically substituted monomercomprises dipentaerythritol tetracrylate.
 62. The method of claim 41,wherein the second composition further comprises an organic solvent. 63.The method of claim 41, further comprising forming a hardcoat layer onthe surface of the plastic eyeglass lens prior to applying the firstcomposition to the surface of the plastic eyeglass lens.
 64. The methodof claim 63, wherein forming a hardcoat layer on the surface of theplastic eyeglass lens comprises: applying an ultraviolet light curablehardcoat composition to the surface of the plastic eyeglass lens; anddirecting ultraviolet light toward the hardcoat composition, wherein theultraviolet light initiates curing of the hardcoat composition to formthe hardcoat layer.
 65. The method of claim 41, wherein applying thehardcoat composition to the surface of the plastic eyeglass lenscomprises rotating the plastic eyeglass lens while directing thehardcoat composition toward the plastic eyeglass lens.
 66. The method ofclaim 41, wherein applying the first composition comprises directing thefirst composition toward the plastic eyeglass lens while rotating theplastic eyeglass lens.
 67. The method of claim 41, wherein applying thesecond composition comprises directing the second composition toward theplastic eyeglass lens while rotating the plastic eyeglass lens.
 68. Themethod of claim 41, wherein ultraviolet light is directed toward thesecond composition for a time of less than about 90 seconds.
 69. Themethod of claim 41, further comprising heating the plastic eyeglass lensat a temperature of between about 40° C. and about 140° C. for a time ofless than about 10 minutes.
 70. The method of claim 41, wherein applyingthe first composition to the plastic eyeglass lens substrate comprises:applying a first portion of the first composition to the plasticeyeglass lens; drying the first portion of the first composition;applying a second portion of the first composition to the dried firstportion; and drying the second portion of the first composition.
 71. Themethod of claim 41, wherein the ultraviolet light is produced by agermicidal lamp.
 72. The method of claim 41, wherein the ultravioletlight is produced by a flash lamp.
 73. The method of claim 41, furthercomprising forming a hardcoat layer upon the surface of the plasticeyeglass lens prior to forming the first coating layer.
 74. The methodof claim 41, wherein the first composition is applied to a front surfaceof the plastic eyeglass lens.
 75. The method of claim 41, wherein thefirst composition is applied to a back surface of the plastic eyeglasslens.
 76. The method of claim 41, wherein the first composition isapplied to a front surface and a back surface of the plastic eyeglasslens.
 77. The method of claim 41, wherein a thickness of the firstcoating layer and the second coating layer, combined, is less than about500 nm.
 78. The method of claim 41, wherein the antireflective coatingis formed in less than about 10 min.
 79. A method for forming an atleast partially antireflective coating on a lens, comprising: applying afirst composition to at least one surface of the lens to form a firstcoating layer, the first composition comprising a first metal alkoxide;applying a silicon containing composition to the first composition toform a silicon layer, the silicon containing composition comprisingcolloidal silicon or a silane monomer; applying a second composition tothe silicon layer, the second composition comprising an an ethylenicallysubstituted monomer and a second metal alkoxide, wherein the secondcomposition is curable by the application of ultraviolet light; anddirecting ultraviolet light toward the second composition, wherein theultraviolet light initiates curing of the second composition to form asecond coating layer.
 80. The method of claim 79, wherein the firstcomposition is curable by the application of ultraviolet light.
 81. Themethod of claim 79, further comprising directing ultraviolet lighttoward the first composition, wherein the ultraviolet light initiatescuring of the first composition to form the first coating layer.
 82. Themethod of claim 79, further comprising heating the first composition,wherein heating the first composition initiates curing of the firstcomposition to form the first coating layer.
 83. The method of claim 79,wherein the first coating layer has an index of refraction that isgreater than an index of refraction of the lens.
 84. The method of claim79, wherein the second coating layer has an index of refraction that isless than an index of refraction of the first coating layer.
 85. Themethod of claim 79, wherein the first coating layer has an index ofrefraction that is greater than an index of refraction of the lens, andwherein the second coating layer has an index of refraction that is lessthan an index of refraction of the first coating layer.
 86. The methodof claim 79, wherein the first and second metal alkoxides have thegeneral formula M (Y)_(p) wherein M is titanium, aluminum, zirconium,boron, tin, indium, antimony, or zinc, Y is a C₁-C₁₀ alkoxy oracetylacetonate, and p is an integer equivalent to the valence of M. 87.The method of claim 79, wherein the first and second metal alkoxideshave the general formula Ti(OR)₄, where R is a C₁-C₁₀ alkyl.
 88. Themethod of claim 79, wherein the first and second metal alkoxides aretitanium methoxide, titanium ethoxide, titanium isopropoxide, titaniumbutoxide, or titanium allylacetoacetate triisopropoxide.
 89. The methodof claim 79, wherein the first composition further comprises aphotoinitiator.
 90. The method of claim 79, wherein the lens is aplastic eyeglass lens.
 91. The method of claim 79, wherein the lens is aglass lens.
 92. The method of claim 79, wherein the first compositionfurther comprises a coinitiator.
 93. The method of claim 79, wherein thefirst composition further comprises an ethylenically substitutedmonomer.
 94. The method of claim 79, wherein the first compositionfurther comprises an organic solvent.
 95. The method of claim 79,wherein the second composition further comprises a fluoroacrylate. 96.The method of claim 79, wherein the second metal alkoxide is a titaniumalkoxide.
 97. The method of claim 79, wherein the second metal alkoxideis an aluminum alkoxide.
 98. The method of claim 79, wherein the secondcomposition further comprises a photoinitiator.
 99. The method of claim79, wherein the ethylenically substituted monomer comprisesdipentaerythritol tetracrylate.
 100. The method of claim 79, wherein thesecond composition further comprises an organic solvent.
 101. The methodof claim 79, further comprising forming a hardcoat layer on the surfaceof the lens prior to applying the first composition to the surface ofthe lens.
 102. The method of claim 100, wherein forming a hardcoat layeron the surface of the lens comprises: applying an ultraviolet lightcurable hardcoat composition to the surface of the lens; and directingultraviolet light toward the hardcoat composition, wherein theultraviolet light initiates curing of the hardcoat composition to formthe hardcoat layer.
 103. The method of claim 79, wherein applying thehardcoat composition to the surface of the lens comprises rotating thelens while directing the hardcoat composition toward the lens.
 104. Themethod of claim 79, wherein applying the first composition comprisesdirecting the first composition toward the lens while rotating the lens.105. The method of claim 79, wherein applying the second compositioncomprises directing the second composition toward the lens whilerotating the lens.
 106. The method of claim 79, wherein ultravioletlight is directed toward the second composition for a time of less thanabout 90 seconds.
 107. The method of claim 79, further comprisingheating the lens at a temperature of between about 40° C. and about 140°C. for a time of less than about 10 minutes.
 108. The method of claim79, wherein applying the first composition to the lens comprises:applying a first portion of the first composition to the lens; dryingthe first portion of the first composition; applying a second portion ofthe first composition to the dried first portion; and drying the secondportion of the first composition.
 109. The method of claim 79, whereinthe ultraviolet light is produced by a germicidal lamp.
 110. The methodof claim 79, wherein the ultraviolet light is produced by a flash lamp.111. The method of claim 79, further comprising forming a hardcoat layerupon the surface of the lens prior to forming the first coating layer.112. The method of claim 79, wherein the first composition is applied toa front surface of the lens.
 113. The method of claim 79, wherein thefirst composition is applied to a back surface of the lens.
 114. Themethod of claim 79, wherein the first composition is applied to a frontsurface and a back surface of the lens.
 115. The method of claim 79,wherein a thickness of the first coating layer and the second coatinglayer, combined, is less than about 500 nm.
 116. The method of claim 79,wherein the antireflective coating is formed in less than about 10 min.117. A plastic eyeglass lens comprising an at least partiallyantireflective coating, formed by the method, comprising: applying afirst composition to at least one surface of a non-coated plasticeyeglass lens to form a first coating layer, the first compositioncomprising a first metal alkoxide; applying a silicon containingcomposition to the first composition to form a silicon layer, thesilicon containing composition comprising colloidal silicon or a silanemonomer; applying a second composition to the first coating layer, thesecond composition comprising an ethylenically substituted monomer and asecond metal alkoxide, wherein the second composition is curable by theapplication of ultraviolet light; and directing ultraviolet light towardthe second composition, wherein the ultraviolet light initiates curingof the second composition to form a second coating layer.
 118. Themethod of claim 117, wherein the first composition is curable by theapplication of ultraviolet light.
 119. The method of claim 117, furthercomprising directing ultraviolet light toward the first composition,wherein the ultraviolet light initiates curing of the first compositionto form the first coating layer.
 120. The method of claim 117, furthercomprising heating the first composition, wherein heating the firstcomposition initiates curing of the first composition to form the firstcoating layer.
 121. The method of claim 117, wherein the first coatinglayer has an index of refraction that is greater than an index ofrefraction of the plastic eyeglass lens.
 122. The method of claim 117,wherein the second coating layer has an index of refraction that is lessthan an index of refraction of the first coating layer.
 123. The methodof claim 117, wherein the first coating layer has an index of refractionthat is greater than an index of refraction of the plastic eyeglasslens, and wherein the second coating layer has an index of refractionthat is less than an index of refraction of the first coating layer.124. The method of claim 117, wherein the first and second metalalkoxides have the general formula M (Y)_(p) wherein M is titanium,aluminum, zirconium, boron, tin, indium, antimony, or zinc, Y is aC₁-C₁₀ alkoxy or acetylacetonate, and p is an integer equivalent to thevalence of M.
 125. The method of claim 117, wherein the first and secondmetal alkoxides have the general formula Ti(OR)₄ where R is a C₁-C₁₀alkyl.
 126. The method of claim 117, wherein the first and second metalalkoxides are titanium methoxide, titanium ethoxide, titaniumisopropoxide, titanium butoxide, or titanium allylacetoacetatetriisopropoxide.
 127. The method of claim 117, wherein the firstcomposition further comprises a photoinitiator.
 128. The method of claim117, wherein the first composition further comprises a coinitiator. 129.The method of claim 117, wherein the first composition further comprisesan ethylenically substituted monomer.
 130. The method of claim 117,wherein the first composition further comprises an organic solvent. 131.The method of claim 117, wherein the second composition furthercomprises a fluoroacrylate.
 132. The method of claim 117, wherein thesecond metal alkoxide is a titanium alkoxide.
 133. The method of claim117, wherein the second metal alkoxide is an aluminum alkoxide.
 134. Themethod of claim 117, wherein the second composition further comprises aphotoinitiator.
 135. The method of claim 117, wherein the ethylenicallysubstituted monomer comprises dipentaerythritol tetracrylate.
 136. Themethod of claim 117, wherein the second composition further comprises anorganic solvent.
 137. The method of claim 117, further comprisingforming a hardcoat layer on the surface of the lens prior to applyingthe first composition to the surface of the plastic eyeglass lens. 138.The method of claim 137, wherein forming a hardcoat layer on the surfaceof the plastic eyeglass lens comprises: applying an ultraviolet lightcurable hardcoat composition to the surface of the plastic eyeglasslens; and directing ultraviolet light toward the hardcoat composition,wherein the ultraviolet light initiates curing of the hardcoatcomposition to form the hardcoat layer.
 139. The method of claim 117,wherein applying the hardcoat composition to the surface of the plasticeyeglass lens comprises rotating the lens while directing the hardcoatcomposition toward the plastic eyeglass lens.
 140. The method of claim117, wherein applying the first composition comprises directing thefirst composition toward the plastic eyeglass lens while rotating theplastic eyeglass lens.
 141. The method of claim 117, wherein applyingthe second composition comprises directing the second composition towardthe plastic eyeglass lens while rotating the plastic eyeglass lens. 142.The method of claim 117, wherein ultraviolet light is directed towardthe second composition for a time of less than about 90 seconds. 143.The method of claim 117, further comprising heating the plastic eyeglasslens at a temperature of between about 40° C. and about 140° C. for atime of less than about 10 minutes.
 144. The method of claim 117,wherein applying the first composition to the plastic eyeglass lenscomprises: applying a first portion of the first composition to theplastic eyeglass lens; drying the first portion of the firstcomposition; applying a second portion of the first composition to thedried first portion; and drying the second portion of the firstcomposition.
 145. The method of claim 117, wherein the ultraviolet lightis produced by a germicidal lamp.
 146. The method of claim 117, whereinthe ultraviolet light is produced by a flash lamp.
 147. The method ofclaim 117, further comprising forming a hardcoat layer upon the surfaceof the plastic eyeglass lens prior to forming the first coating layer.148. The method of claim 117, wherein the first composition is appliedto a front surface of the plastic eyeglass lens.
 149. The method ofclaim 117, wherein the first composition is applied to a back surface ofthe plastic eyeglass lens.
 150. The method of claim 117, wherein thefirst composition is applied to a front surface and a back surface ofthe plastic eyeglass lens.
 151. The method of claim 117, wherein athickness of the first coating layer and the second coating layer,combined, is less than about 500 nm.
 152. The method of claim 117,wherein the antireflective coating is formed in less than about 10 min.